diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index b66c6da..e208bf2 100644
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -3790,9 +3790,11 @@ char *PQcmdTuples(PGresult *res);
PGresult. This function can only be used following
the execution of a SELECT, CREATE TABLE AS,
INSERT, UPDATE, DELETE,
- MOVE, FETCH, or COPY statement,
- or an EXECUTE of a prepared query that contains an
- INSERT, UPDATE, or DELETE statement.
+ MERGE, MOVE, FETCH,
+ or COPY statement, or an EXECUTE of a
+ prepared query that contains an INSERT,
+ UPDATE, DELETE
+ or MERGE statement.
If the command that generated the PGresult was anything
else, PQcmdTuples returns an empty string. The caller
should not free the return value directly. It will be freed when
diff --git a/doc/src/sgml/mvcc.sgml b/doc/src/sgml/mvcc.sgml
index 24613e3..9467d1a 100644
--- a/doc/src/sgml/mvcc.sgml
+++ b/doc/src/sgml/mvcc.sgml
@@ -423,6 +423,30 @@ COMMIT;
+ The MERGE allows the user to specify various combinations
+ of INSERT, UPDATE or
+ DELETE subcommands. A MERGE command
+ with both INSERT and UPDATE
+ subcommands looks similar to INSERT with an
+ ON CONFLICT DO UPDATE clause but does not guarantee
+ that either INSERT and UPDATE will occur.
+
+ Current behavior of patch:
+
+The SQl Standard says "The extent to which an SQL-implementation may disallow independent changes that are not significant is implementation-defined.", SQL-2016 Foundation, p.1178, 4) "not significant" is undefined. The following concurrency rules are included within v14.
+
+If MERGE attempts an UPDATE or DELETE and the row is concurrently updated, then MERGE will behave the same as the UPDATE or DELETE commands and perform its action on the latest version of the row, using standard EvalPlanQual. MERGE actions can be conditional, so conditions must be re-evaluated on the latest row.
+
+If MERGE attempts an UPDATE or DELETE and the row is concurrently deleted we currently throw an ERROR. We now agree it is possible and desirable to attempt an INSERT in this case, but haven't yet worked out how.
+
+If MERGE attempts an INSERT and a unique index is present and the new row is a duplicate then a uniqueness violation is raised. MERGE does not attempt to avoid the ERROR by attempting an UPDATE. It woud be possible to avoid the errors by using speculative inserts but that has been argued against by some.
+
+The full guarantee of always either insert or update that is available with INSERT ON CONFLICT UPDATE is not always possible because of the conditional rules of the MERGE statement, so we would be able to make only one attempt at UPDATE if INSERT fails or INSERT if UPDATE fails. This is to ensure consistent behavior of the command.
+
+It is understood that other DBMS throw errors in these case (fact check needed). Some DBMS cope with this by routing such errors to an Error Table that is created on first error.
+
+
+
Because Read Committed mode starts each command with a new snapshot
that includes all transactions committed up to that instant,
subsequent commands in the same transaction will see the effects
@@ -900,7 +924,8 @@ ERROR: could not serialize access due to read/write dependencies among transact
The commands UPDATE,
- DELETE, and INSERT
+ DELETE, INSERT and
+ MERGE
acquire this lock mode on the target table (in addition to
ACCESS SHARE locks on any other referenced
tables). In general, this lock mode will be acquired by any
diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
index c1e3c6a..e74d719 100644
--- a/doc/src/sgml/plpgsql.sgml
+++ b/doc/src/sgml/plpgsql.sgml
@@ -1246,7 +1246,7 @@ EXECUTE format('SELECT count(*) FROM %I '
Another restriction on parameter symbols is that they only work in
SELECT, INSERT, UPDATE, and
- DELETE commands. In other statement
+ DELETE and MERGE commands. In other statement
types (generically called utility statements), you must insert
values textually even if they are just data values.
@@ -1529,6 +1529,7 @@ GET DIAGNOSTICS integer_var = ROW_COUNT;
UPDATE, INSERT, and DELETE
+ and MERGE
statements set FOUND true if at least one
row is affected, false if no row is affected.
diff --git a/doc/src/sgml/ref/allfiles.sgml b/doc/src/sgml/ref/allfiles.sgml
index 22e6893..4e01e56 100644
--- a/doc/src/sgml/ref/allfiles.sgml
+++ b/doc/src/sgml/ref/allfiles.sgml
@@ -159,6 +159,7 @@ Complete list of usable sgml source files in this directory.
+
diff --git a/doc/src/sgml/ref/insert.sgml b/doc/src/sgml/ref/insert.sgml
index 134092f..77dc110 100644
--- a/doc/src/sgml/ref/insert.sgml
+++ b/doc/src/sgml/ref/insert.sgml
@@ -571,6 +571,13 @@ INSERT oid count
+
+
+ You may also wish to consider using MERGE, since that
+ allows mixed INSERT, UPDATE and
+ DELETE within a single statement.
+ See .
+
@@ -741,7 +748,9 @@ INSERT INTO distributors (did, dname) VALUES (10, 'Conrad International')
Also, the case in
which a column name list is omitted, but not all the columns are
filled from the VALUES clause or query,
- is disallowed by the standard.
+ is disallowed by the standard. If you prefer a more SQL Standard
+ conforming statement than ON CONFLICT, see
+ .
diff --git a/doc/src/sgml/ref/merge.sgml b/doc/src/sgml/ref/merge.sgml
new file mode 100644
index 0000000..9a8415e
--- /dev/null
+++ b/doc/src/sgml/ref/merge.sgml
@@ -0,0 +1,605 @@
+
+
+
+
+
+ MERGE
+ 7
+ SQL - Language Statements
+
+
+
+ MERGE
+ insert, update, or delete rows of a table based upon source data
+
+
+
+
+MERGE INTO target_table_name [ [ AS ] target_alias ]
+USING data_source
+ON join_condition
+when_clause [...]
+
+where data_source is
+
+{ source_table_name |
+ ( source_query )
+}
+[ [ AS ] source_alias ]
+
+and when_clause is
+
+{ WHEN MATCHED [ AND condition ] THEN { merge_update | merge_delete } |
+ WHEN NOT MATCHED [ AND condition ] THEN { merge_insert | DO NOTHING }
+}
+
+and merge_update is
+
+UPDATE SET { column_name = { expression | DEFAULT } |
+ ( column_name [, ...] ) = ( { expression | DEFAULT } [, ...] )
+ } [, ...]
+
+and merge_insert is
+
+INSERT [( column_name [, ...] )]
+[ OVERRIDING { SYSTEM | USER } VALUE ]
+{ VALUES ( { expression | DEFAULT } [, ...] ) | DEFAULT VALUES }
+
+and merge_delete is
+
+DELETE
+
+
+
+
+ Description
+
+
+ MERGE performs actions that modify rows in the
+ target_table_name,
+ using the data_source.
+ MERGE provides a single SQL
+ statement that can conditionally INSERT,
+ UPDATE or DELETE rows, a task
+ that would otherwise require multiple procedural language statements.
+
+
+
+ First, the MERGE command performs a left outer join
+ from data_source to
+ target_table_name
+ producing zero or more candidate change rows. For each candidate change
+ row the status of MATCHED or NOT MATCHED is set
+ just once, after which WHEN clauses are evaluated
+ in the order specified. If one of them is activated, the specified
+ action occurs. No more than one WHEN clause can be
+ activated for any candidate change row.
+
+
+
+ MERGE actions have the same effect as
+ regular UPDATE, INSERT, or
+ DELETE commands of the same names. The syntax of
+ those commands is different, notably that there is no WHERE
+ clause and no tablename is specified. All actions refer to the
+ target_table_name,
+ though modifications to other tables may be made using triggers.
+
+
+
+ There is no MERGE privilege.
+ You must have the UPDATE privilege on the column(s)
+ of the target_table_name
+ referred to in the SET clause
+ if you specify an update action, the INSERT privilege
+ on the target_table_name
+ if you specify an insert action and/or the DELETE
+ privilege on the target_table_name
+ if you specify a delete action on the
+ target_table_name.
+ Privileges are tested once at statement start and are checked
+ whether or not particular WHEN clauses are activated
+ during the subsequent execution.
+ You will require the SELECT privilege on the
+ data_source and any column(s)
+ of the target_table_name
+ referred to in a condition.
+
+
+
+
+ Parameters
+
+
+
+ target_table_name
+
+
+ The name (optionally schema-qualified) of the target table or materialized
+ view to merge into.
+
+
+
+
+
+ target_alias
+
+
+ A substitute name for the target table. When an alias is
+ provided, it completely hides the actual name of the table. For
+ example, given MERGE foo AS f, the remainder of the
+ MERGE statement must refer to this table as
+ f not foo.
+
+
+
+
+
+ source_table_name
+
+
+ The name (optionally schema-qualified) of the source table, view or
+ transition table.
+
+
+
+
+
+ source_query
+
+
+ A query (SELECT statement or VALUES
+ statement) that supplies the rows to be merged into the
+ target_table_name.
+ Refer to the
+ statement or
+ statement for a description of the syntax.
+
+
+
+
+
+ source_alias
+
+
+ A substitute name for the data source. When an alias is
+ provided, it completely hides whether table or query was specified.
+
+
+
+
+
+ join_condition
+
+
+ join_condition is
+ an expression resulting in a value of type
+ boolean (similar to a WHERE
+ clause) that specifies which rows in the
+ data_source
+ match rows in the
+ target_table_name.
+
+
+
+
+
+ when_clause
+
+
+ At least one WHEN clause is required.
+
+
+ If the WHEN clause specifies WHEN MATCHED
+ and the candidate change row matches a row in the
+ target_table_name
+ the WHEN clause is activated if the
+ condition is
+ absent or is present and evaluates to true.
+ If the WHEN clause specifies WHEN NOT MATCHED
+ and the candidate change row does not match a row in the
+ target_table_name
+ the WHEN clause is activated if the
+ condition is
+ absent or is present and evaluates to true.
+
+
+
+
+
+ condition
+
+
+ An expression that returns a value of type boolean.
+ If this expression returns true then the WHEN
+ clause will be activated and the corresponding action will occur for
+ that row. The expression may not contain functions that possibly performs
+ writes to the database.
+
+
+ A condition on a WHEN MATCHED clause can refer to columns
+ in both the source and the target relation. A condition on a
+ WHEN NOT MATCHED clause can only refer to columns from
+ the source relation, since by definition there is no matching target row.
+ A condition cannot contain subqueries, set returning functions,
+ nor can it contain window or aggregate functions. Only the system
+ attributes tableoid and oid are accessible.
+
+
+
+
+
+ merge_insert
+
+
+ The specification of an INSERT action that inserts
+ one row into the target table.
+ The target column names can be listed in any order. If no list of
+ column names is given at all, the default is all the columns of the
+ table in their declared order.
+
+
+ Each column not present in the explicit or implicit column list will be
+ filled with a default value, either its declared default value
+ or null if there is none.
+
+
+ If the expression for any column is not of the correct data type,
+ automatic type conversion will be attempted.
+
+
+ If target_table_name
+ is a partitioned table, each row is routed to the appropriate partition
+ and inserted into it.
+ If target_table_name
+ is a partition, an error will occur if one of the input rows violates
+ the partition constraint.
+
+
+ Do not include the table name, as you would normally do with an
+ command.
+ For example, INSERT INTO tab VALUES (1, 50) is invalid.
+ Column names may not be specified more than once.
+ INSERT actions cannot contain sub-selects.
+
+
+ The VALUES clause can only refer to columns from
+ the source relation, since by definition there is no matching target row.
+ The VALUES clause cannot contain subqueries, set
+ returning functions, nor can it contain window or aggregate functions.
+
+
+
+
+
+ merge_update
+
+
+ The specification of an UPDATE action that updates
+ the current row of the target_table_name.
+ Column names may not be specified more than once.
+
+
+ Do not include the table name, as you would normally do with an
+ command.
+ For example, UPDATE tab SET col = 1 is invalid. Also,
+ do not include a WHERE clause, since only the current
+ row can be updated. For example,
+ UPDATE SET col = 1 WHERE key = 57 is invalid.
+ UPDATE actions cannot contain sub-selects in the
+ SET clause.
+
+
+
+
+
+ merge_delete
+
+
+ Specifies a DELETE action that deletes the current row
+ of the target_table_name.
+ Do not include the tablename or any other clauses, as you would normally
+ do with an command.
+
+
+
+
+
+ column_name
+
+
+ The name of a column in the target_table_name. The column name
+ can be qualified with a subfield name or array subscript, if
+ needed. (Inserting into only some fields of a composite
+ column leaves the other fields null.) When referencing a
+ column, do not include the table's name in the specification
+ of a target column.
+
+
+
+
+
+ OVERRIDING SYSTEM VALUE
+
+
+ Without this clause, it is an error to specify an explicit value
+ (other than DEFAULT) for an identity column defined
+ as GENERATED ALWAYS. This clause overrides that
+ restriction.
+
+
+
+
+
+ OVERRIDING USER VALUE
+
+
+ If this clause is specified, then any values supplied for identity
+ columns defined as GENERATED BY DEFAULT are ignored
+ and the default sequence-generated values are applied.
+
+
+
+
+
+ DEFAULT VALUES
+
+
+ All columns will be filled with their default values.
+ (An OVERRIDING clause is not permitted in this
+ form.)
+
+
+
+
+
+ expression
+
+
+ An expression to assign to the column. The expression can use the
+ old values of this and other columns in the table.
+
+
+
+
+
+ DEFAULT
+
+
+ Set the column to its default value (which will be NULL if no
+ specific default expression has been assigned to it).
+
+
+
+
+
+
+
+
+ Outputs
+
+
+ On successful completion, a MERGE command returns a command
+ tag of the form
+
+MERGE total-count
+
+ The total-count is the total
+ number of rows changed (whether updated, inserted or deleted).
+ If total-count is 0, no rows
+ were changed in any way.
+
+
+
+ The number of rows inserted, updated and deleted can be seen in the output of
+ EXPLAIN ANALYZE.
+
+
+
+
+ Execution
+
+
+ The following steps take place during the execution of
+ MERGE.
+
+
+
+ Perform any BEFORE STATEMENT triggers for all actions specified, whether or
+ not their WHEN clauses are activated during execution.
+
+
+
+
+ Perform left outer join from source to target table. If the MERGE
+ contains no INSERT actions that is optimized to be an inner join.
+ If the USING clause contains a scalar sub-query we avoid the
+ join completely. The resulting query will be optimized normally and will produce
+ a set of candidate change row. For each candidate change row
+
+
+
+ Evaluate whether each row is MATCHED or NOT MATCHED.
+
+
+
+
+ Test each WHEN condition in the order specified until one activates.
+
+
+
+
+ When activated, perform the following actions
+
+
+
+ Perform any BEFORE ROW triggers that fire for the action's event type.
+
+
+
+
+ Apply the action specified, invoking any check constraints on the
+ target table.
+ However, it will not invoke rules.
+
+
+
+
+ Perform any AFTER ROW triggers that fire for the action's event type.
+
+
+
+
+
+
+
+
+
+
+ Perform any AFTER STATEMENT triggers for actions specified, whether or
+ not they actually occur. This is similar to the behavior of an
+ UPDATE statement that modifies no rows.
+
+
+
+ In summary, statement triggers for an event type (say, INSERT) will
+ be fired whenever we specify an action of that kind. Row-level
+ triggers will fire only for the one event type activated.
+ So a MERGE might fire statement triggers for both
+ UPDATE and INSERT, even though only
+ UPDATE row triggers were fired.
+
+
+
+ You should ensure that the join produces at most one candidate change row
+ for each target row. In other words, a target row shouldn't join to more
+ than one data source row. If it does, then only one of the candidate change
+ rows will be used to modify the target row, later attempts to modify will
+ cause an error. This can also occur if row triggers make changes to the
+ target table which are then subsequently modified by MERGE.
+ If the repeated action is an INSERT this will
+ cause a uniqueness violation while a repeated UPDATE or
+ DELETE will cause a cardinality violation; the latter behavior
+ is required by the SQL Standard. This differs from
+ historical PostgreSQL behavior of joins in
+ UPDATE and DELETE statements where second and
+ subsequent attempts to modify are simply ignored.
+
+
+
+ If a WHEN clause omits an AND clause it becomes
+ the final reachable clause of that kind (MATCHED or
+ NOT MATCHED). If a later WHEN clause of that kind
+ is specified it would be provably unreachable and an error is raised.
+ If a final reachable clause is omitted it is possible that no action
+ will be taken for a candidate change row - it should be noted that no error
+ is raised if that occurs.
+
+
+
+
+ Notes
+
+
+ The order in which rows are generated from the data source is indeterminate
+ by default. A source_query
+ can be used to specify a consistent ordering, if required, which might be
+ needed to avoid deadlocks between concurrent transactions.
+
+
+
+ There is no RETURNING clause with MERGE.
+ Actions of INSERT, UPDATE and DELETE
+ cannot contain RETURNING or WITH clauses.
+
+
+
+ MERGE cannot be used against tables with row security, nor will
+ it operate on tables with inheritance or partitioning. MERGE can
+ use a transition table as a source, but it cannot be used on a target table that has
+ statement triggers that require a transition table.
+ These restrictions may be lifted in later releases.
+
+
+
+ You may also wish to consider using INSERT ... ON CONFLICT as an
+ alternative statement which offers the ability to run an UPDATE
+ if a concurrent INSERT occurs. There are a variety of
+ differences and restrictions between the two statement types and they are not
+ interchangeable. See .
+
+
+
+
+ Examples
+
+
+ Perform maintenance on CustomerAccounts based upon new Transactions.
+
+
+MERGE CustomerAccount CA
+USING RecentTransactions T
+ON T.CustomerId = CA.CustomerId
+WHEN MATCHED THEN
+ UPDATE SET Balance = Balance + TransactionValue
+WHEN NOT MATCHED THEN
+ INSERT (CustomerId, Balance)
+ VALUES (T.CustomerId, T.TransactionValue)
+;
+
+
+ notice that this would be exactly equivalent to the following
+ statement because the MATCHED result does not change
+ during execution
+
+
+MERGE CustomerAccount CA
+USING (Select CustomerId, TransactionValue From RecentTransactions) AS T
+ON CA.CustomerId = T.CustomerId
+WHEN NOT MATCHED THEN
+ INSERT (CustomerId, Balance)
+ VALUES (T.CustomerId, T.TransactionValue)
+WHEN MATCHED THEN
+ UPDATE SET Balance = Balance + TransactionValue
+;
+
+
+
+
+ Attempt to insert a new stock item along with the quantity of stock. If
+ the item already exists, instead update the stock count of the existing
+ item. Don't allow entries that have zero stock.
+
+MERGE INTO wines w
+USING wine_stock_changes s
+ON s.winename = w.winename
+WHEN NOT MATCHED AND s.stock_delta > 0 THEN
+ INSERT VALUES(s.winename, s.stock_delta)
+WHEN MATCHED AND w.stock + s.stock_delta > 0 THEN
+ UPDATE SET stock = w.stock + s.stock_delta;
+WHEN MATCHED THEN
+ DELETE
+;
+
+
+ The wine_stock_changes table might be, for example, a temporary table
+ recently loaded into the database.
+
+
+
+
+
+ Compatibility
+
+ This command conforms to the SQL standard.
+
+
+ The DO NOTHING action is an extension to the SQL standard.
+
+
+
diff --git a/doc/src/sgml/reference.sgml b/doc/src/sgml/reference.sgml
index d27fb41..ef2270c 100644
--- a/doc/src/sgml/reference.sgml
+++ b/doc/src/sgml/reference.sgml
@@ -186,6 +186,7 @@
&listen;
&load;
&lock;
+ &merge;
&move;
¬ify;
&prepare;
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 18b7471..3dab0b1 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1210,6 +1210,12 @@ XLogInsertRecord(XLogRecData *rdata,
return EndPos;
}
+int64
+GetXactWALBytes(void)
+{
+ return (int64) XactLastRecEnd;
+}
+
/*
* Reserves the right amount of space for a record of given size from the WAL.
* *StartPos is set to the beginning of the reserved section, *EndPos to
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index 20d61f3..9612c13 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -229,9 +229,9 @@ F311 Schema definition statement 02 CREATE TABLE for persistent base tables YES
F311 Schema definition statement 03 CREATE VIEW YES
F311 Schema definition statement 04 CREATE VIEW: WITH CHECK OPTION YES
F311 Schema definition statement 05 GRANT statement YES
-F312 MERGE statement NO consider INSERT ... ON CONFLICT DO UPDATE
-F313 Enhanced MERGE statement NO
-F314 MERGE statement with DELETE branch NO
+F312 MERGE statement YES consider INSERT ... ON CONFLICT DO UPDATE
+F313 Enhanced MERGE statement YES
+F314 MERGE statement with DELETE branch YES
F321 User authorization YES
F341 Usage tables NO no ROUTINE_*_USAGE tables
F361 Subprogram support YES
diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index 900fa74..32ff308 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -896,6 +896,9 @@ ExplainNode(PlanState *planstate, List *ancestors,
case CMD_DELETE:
pname = operation = "Delete";
break;
+ case CMD_MERGE:
+ pname = operation = "Merge";
+ break;
default:
pname = "???";
break;
@@ -2926,6 +2929,10 @@ show_modifytable_info(ModifyTableState *mtstate, List *ancestors,
operation = "Delete";
foperation = "Foreign Delete";
break;
+ case CMD_MERGE:
+ operation = "Merge";
+ foperation = "Foreign Merge";
+ break;
default:
operation = "???";
foperation = "Foreign ???";
@@ -3046,6 +3053,29 @@ show_modifytable_info(ModifyTableState *mtstate, List *ancestors,
ExplainPropertyFloat("Conflicting Tuples", other_path, 0, es);
}
}
+ else if (node->operation == CMD_MERGE)
+ {
+ /* EXPLAIN ANALYZE display of actual outcome for each tuple proposed */
+ if (es->analyze && mtstate->ps.instrument)
+ {
+ double total;
+ double insert_path;
+ double update_path;
+ double delete_path;
+
+ InstrEndLoop(mtstate->mt_plans[0]->instrument);
+
+ /* count the number of source rows */
+ total = mtstate->mt_plans[0]->instrument->ntuples;
+ update_path = mtstate->ps.instrument->nfiltered1;
+ delete_path = mtstate->ps.instrument->nfiltered2;
+ insert_path = total - update_path - delete_path;
+
+ ExplainPropertyFloat("Tuples Inserted", insert_path, 0, es);
+ ExplainPropertyFloat("Tuples Updated", update_path, 0, es);
+ ExplainPropertyFloat("Tuples Deleted", delete_path, 0, es);
+ }
+ }
if (labeltargets)
ExplainCloseGroup("Target Tables", "Target Tables", false, es);
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index b945b15..c3610b1 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -151,6 +151,7 @@ PrepareQuery(PrepareStmt *stmt, const char *queryString,
case CMD_INSERT:
case CMD_UPDATE:
case CMD_DELETE:
+ case CMD_MERGE:
/* OK */
break;
default:
diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c
index 160d941..ab804bf 100644
--- a/src/backend/commands/trigger.c
+++ b/src/backend/commands/trigger.c
@@ -3075,11 +3075,14 @@ ltrmark:;
{
/* it was updated, so look at the updated version */
TupleTableSlot *epqslot;
+ Index rti = relinfo->ri_mergeTargetRTI > 0 ?
+ relinfo->ri_mergeTargetRTI :
+ relinfo->ri_RangeTableIndex;
epqslot = EvalPlanQual(estate,
epqstate,
relation,
- relinfo->ri_RangeTableIndex,
+ rti,
lockmode,
&hufd.ctid,
hufd.xmax);
@@ -4433,6 +4436,16 @@ MakeTransitionCaptureState(TriggerDesc *trigdesc, Oid relid, CmdType cmdType)
need_old = trigdesc->trig_delete_old_table;
need_new = false;
break;
+ case CMD_MERGE:
+ if (trigdesc->trig_insert_new_table ||
+ trigdesc->trig_update_new_table ||
+ trigdesc->trig_update_old_table ||
+ trigdesc->trig_delete_old_table)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("MERGE on table with transition capture triggers is not implemented")));
+ need_old = need_new = false;
+ break;
default:
elog(ERROR, "unexpected CmdType: %d", (int) cmdType);
need_old = need_new = false; /* keep compiler quiet */
diff --git a/src/backend/executor/README b/src/backend/executor/README
index b3e74aa..3cef654 100644
--- a/src/backend/executor/README
+++ b/src/backend/executor/README
@@ -37,6 +37,14 @@ the plan tree returns the computed tuples to be updated, plus a "junk"
one. For DELETE, the plan tree need only deliver a CTID column, and the
ModifyTable node visits each of those rows and marks the row deleted.
+MERGE runs one generic plan that returns candidate target rows. Each row
+consists of a super-row that contains all the columns needed by any of the
+individual actions, plus a CTID junk column. If the CTID column is set we
+attempt to activate WHEN MATCHED actions, or if it is NULL then we will
+attempt to activate WHEN NOT MATCHED actions. Once we know which action
+is activated we form the final result row and apply only those changes,
+so we project twice for each result row.
+
XXX a great deal more documentation needs to be written here...
diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c
index 5d3e923..bfaafa3 100644
--- a/src/backend/executor/execMain.c
+++ b/src/backend/executor/execMain.c
@@ -232,6 +232,7 @@ standard_ExecutorStart(QueryDesc *queryDesc, int eflags)
case CMD_INSERT:
case CMD_DELETE:
case CMD_UPDATE:
+ case CMD_MERGE:
estate->es_output_cid = GetCurrentCommandId(true);
break;
@@ -2195,6 +2196,19 @@ ExecWithCheckOptions(WCOKind kind, ResultRelInfo *resultRelInfo,
errmsg("new row violates row-level security policy for table \"%s\"",
wco->relname)));
break;
+ case WCO_RLS_MERGE_UPDATE_CHECK:
+ case WCO_RLS_MERGE_DELETE_CHECK:
+ if (wco->polname != NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+ errmsg("target row violates row-level security policy \"%s\" (USING expression) for table \"%s\"",
+ wco->polname, wco->relname)));
+ else
+ ereport(ERROR,
+ (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+ errmsg("target row violates row-level security policy (USING expression) for table \"%s\"",
+ wco->relname)));
+ break;
case WCO_RLS_CONFLICT_CHECK:
if (wco->polname != NULL)
ereport(ERROR,
@@ -2820,6 +2834,7 @@ EvalPlanQualInit(EPQState *epqstate, EState *estate,
epqstate->plan = subplan;
epqstate->arowMarks = auxrowmarks;
epqstate->epqParam = epqParam;
+ epqstate->epqresult = EPQ_UNUSED;
}
/*
diff --git a/src/backend/executor/execPartition.c b/src/backend/executor/execPartition.c
index 4048c3e..bd430d8 100644
--- a/src/backend/executor/execPartition.c
+++ b/src/backend/executor/execPartition.c
@@ -59,6 +59,7 @@ ExecSetupPartitionTupleRouting(ModifyTableState *mtstate,
int num_update_rri = 0,
update_rri_index = 0;
bool is_update = false;
+ bool is_merge = false;
PartitionTupleRouting *proute;
/*
@@ -79,10 +80,14 @@ ExecSetupPartitionTupleRouting(ModifyTableState *mtstate,
/* Set up details specific to the type of tuple routing we are doing. */
if (mtstate && mtstate->operation == CMD_UPDATE)
+ is_update = true;
+ else if (mtstate && mtstate->operation == CMD_MERGE)
+ is_merge = true;
+
+ if (is_update || is_merge)
{
ModifyTable *node = (ModifyTable *) mtstate->ps.plan;
- is_update = true;
update_rri = mtstate->resultRelInfo;
num_update_rri = list_length(node->plans);
proute->subplan_partition_offsets =
@@ -95,7 +100,8 @@ ExecSetupPartitionTupleRouting(ModifyTableState *mtstate,
*/
proute->root_tuple_slot = MakeTupleTableSlot();
}
- else
+
+ if (!is_update || is_merge)
{
/*
* Since we are inserting tuples, we need to create all new result
@@ -122,7 +128,7 @@ ExecSetupPartitionTupleRouting(ModifyTableState *mtstate,
TupleDesc part_tupdesc;
Oid leaf_oid = lfirst_oid(cell);
- if (is_update)
+ if (is_update || is_merge)
{
/*
* If the leaf partition is already present in the per-subplan
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 2a8ecbd..b83f611 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -261,6 +261,7 @@ ExecInsert(ModifyTableState *mtstate,
List *arbiterIndexes,
OnConflictAction onconflict,
EState *estate,
+ MergeActionState *actionState,
bool canSetTag)
{
HeapTuple tuple;
@@ -472,9 +473,17 @@ ExecInsert(ModifyTableState *mtstate,
* partition, we should instead check UPDATE policies, because we are
* executing policies defined on the target table, and not those
* defined on the child partitions.
+ *
+ * If we're running MERGE, we refer to the action that we're executing
+ * to know if we're doing an INSERT or UPDATE to a partition table.
*/
- wco_kind = (mtstate->operation == CMD_UPDATE) ?
- WCO_RLS_UPDATE_CHECK : WCO_RLS_INSERT_CHECK;
+ if (mtstate->operation == CMD_UPDATE)
+ wco_kind = WCO_RLS_UPDATE_CHECK;
+ else if (mtstate->operation == CMD_INSERT)
+ wco_kind = WCO_RLS_INSERT_CHECK;
+ else if (mtstate->operation == CMD_MERGE)
+ wco_kind = (actionState->commandType == CMD_UPDATE) ?
+ WCO_RLS_UPDATE_CHECK : WCO_RLS_INSERT_CHECK;
/*
* ExecWithCheckOptions() will skip any WCOs which are not of the kind
@@ -707,10 +716,12 @@ ExecDelete(ModifyTableState *mtstate,
ItemPointer tupleid,
HeapTuple oldtuple,
TupleTableSlot *planSlot,
+ bool error_on_SelfUpdate,
EPQState *epqstate,
EState *estate,
bool *tupleDeleted,
bool processReturning,
+ MergeActionState *actionState,
bool canSetTag)
{
ResultRelInfo *resultRelInfo;
@@ -719,6 +730,7 @@ ExecDelete(ModifyTableState *mtstate,
HeapUpdateFailureData hufd;
TupleTableSlot *slot = NULL;
TransitionCaptureState *ar_delete_trig_tcs;
+ ExprContext *econtext = mtstate->ps.ps_ExprContext;
if (tupleDeleted)
*tupleDeleted = false;
@@ -803,6 +815,7 @@ ldelete:;
estate->es_crosscheck_snapshot,
true /* wait for commit */ ,
&hufd);
+
switch (result)
{
case HeapTupleSelfUpdated:
@@ -810,11 +823,23 @@ ldelete:;
/*
* The target tuple was already updated or deleted by the
* current command, or by a later command in the current
- * transaction. The former case is possible in a join DELETE
+ * transaction.
+ */
+
+ /*
+ * The former case is possible in a join UPDATE
* where multiple tuples join to the same target tuple. This
- * is somewhat questionable, but Postgres has always allowed
- * it: we just ignore additional deletion attempts.
- *
+ * is pretty questionable, but Postgres has always allowed it:
+ * we just execute the first update action and ignore
+ * additional update attempts. SQLStandard disallows this for
+ * MERGE, so allow the caller to select how to handle this.
+ */
+ if (error_on_SelfUpdate)
+ ereport(ERROR,
+ (errcode(ERRCODE_CARDINALITY_VIOLATION),
+ errmsg("MERGE command cannot affect row a second time")));
+
+ /*
* The latter case arises if the tuple is modified by a
* command in a BEFORE trigger, or perhaps by a command in a
* volatile function used in the query. In such situations we
@@ -851,20 +876,54 @@ ldelete:;
if (!ItemPointerEquals(tupleid, &hufd.ctid))
{
TupleTableSlot *epqslot;
+ Index rti = resultRelInfo->ri_mergeTargetRTI > 0 ?
+ resultRelInfo->ri_mergeTargetRTI :
+ resultRelInfo->ri_RangeTableIndex;
+ /*
+ * Since we generate a RIGHT OUTER JOIN query with a target
+ * table RTE different than the result relation RTE, we
+ * must pass in the RTI of the relation used in the join
+ * query and not the one from result relation.
+ */
epqslot = EvalPlanQual(estate,
epqstate,
resultRelationDesc,
- resultRelInfo->ri_RangeTableIndex,
+ rti,
LockTupleExclusive,
&hufd.ctid,
hufd.xmax);
if (!TupIsNull(epqslot))
{
*tupleid = hufd.ctid;
- goto ldelete;
+ if (actionState == NULL)
+ goto ldelete;
+ else
+ {
+ Datum datum;
+ bool isNull;
+
+ datum = ExecGetJunkAttribute(epqslot, resultRelInfo->ri_junkFilter->jf_junkAttNo, &isNull);
+ if (isNull)
+ epqstate->epqresult = EPQ_TUPLE_IS_NULL;
+ else
+ {
+ epqstate->epqresult = EPQ_TUPLE_IS_NOT_NULL;
+ /*
+ * Also set the source tuple in the inner slot.
+ * That's where ExecProject expects to see.
+ */
+ econtext->ecxt_innertuple = epqslot;
+ }
+ return NULL;
+ }
}
}
+
+ /*
+ * MERGE needs to know the result of any EvalPlanQual.
+ */
+ epqstate->epqresult = EPQ_TUPLE_IS_NULL;
/* tuple already deleted; nothing to do */
return NULL;
@@ -1002,8 +1061,10 @@ ExecUpdate(ModifyTableState *mtstate,
HeapTuple oldtuple,
TupleTableSlot *slot,
TupleTableSlot *planSlot,
+ bool error_on_SelfUpdate,
EPQState *epqstate,
EState *estate,
+ MergeActionState *actionState,
bool canSetTag)
{
HeapTuple tuple;
@@ -1013,6 +1074,7 @@ ExecUpdate(ModifyTableState *mtstate,
HeapUpdateFailureData hufd;
List *recheckIndexes = NIL;
TupleConversionMap *saved_tcs_map = NULL;
+ ExprContext *econtext = mtstate->ps.ps_ExprContext;
/*
* abort the operation if not running transactions
@@ -1149,8 +1211,8 @@ lreplace:;
* Row movement, part 1. Delete the tuple, but skip RETURNING
* processing. We want to return rows from INSERT.
*/
- ExecDelete(mtstate, tupleid, oldtuple, planSlot, epqstate, estate,
- &tuple_deleted, false, false);
+ ExecDelete(mtstate, tupleid, oldtuple, planSlot, false, epqstate,
+ estate, &tuple_deleted, false, NULL, false);
/*
* For some reason if DELETE didn't happen (e.g. trigger prevented
@@ -1210,7 +1272,8 @@ lreplace:;
estate->es_result_relation_info = mtstate->rootResultRelInfo;
ret_slot = ExecInsert(mtstate, slot, planSlot, NULL,
- ONCONFLICT_NONE, estate, canSetTag);
+ ONCONFLICT_NONE, estate, actionState,
+ canSetTag);
/*
* Revert back the active result relation and the active
@@ -1258,12 +1321,23 @@ lreplace:;
/*
* The target tuple was already updated or deleted by the
* current command, or by a later command in the current
- * transaction. The former case is possible in a join UPDATE
+ * transaction.
+ */
+
+ /*
+ * The former case is possible in a join UPDATE
* where multiple tuples join to the same target tuple. This
* is pretty questionable, but Postgres has always allowed it:
* we just execute the first update action and ignore
- * additional update attempts.
- *
+ * additional update attempts. SQLStandard disallows this for
+ * MERGE, so allow the caller to select how to handle this.
+ */
+ if (error_on_SelfUpdate)
+ ereport(ERROR,
+ (errcode(ERRCODE_CARDINALITY_VIOLATION),
+ errmsg("MERGE command cannot affect row a second time")));
+
+ /*
* The latter case arises if the tuple is modified by a
* command in a BEFORE trigger, or perhaps by a command in a
* volatile function used in the query. In such situations we
@@ -1298,22 +1372,81 @@ lreplace:;
if (!ItemPointerEquals(tupleid, &hufd.ctid))
{
TupleTableSlot *epqslot;
+ Index rti = resultRelInfo->ri_mergeTargetRTI > 0 ?
+ resultRelInfo->ri_mergeTargetRTI :
+ resultRelInfo->ri_RangeTableIndex;
+ /*
+ * Since we generate a RIGHT OUTER JOIN query with a target
+ * table RTE different than the result relation RTE, we
+ * must pass in the RTI of the relation used in the join
+ * query and not the one from result relation.
+ */
epqslot = EvalPlanQual(estate,
epqstate,
resultRelationDesc,
- resultRelInfo->ri_RangeTableIndex,
+ rti,
lockmode,
&hufd.ctid,
hufd.xmax);
if (!TupIsNull(epqslot))
{
*tupleid = hufd.ctid;
- slot = ExecFilterJunk(resultRelInfo->ri_junkFilter, epqslot);
- tuple = ExecMaterializeSlot(slot);
- goto lreplace;
+ if (actionState == NULL)
+ {
+ /* Normal UPDATE path */
+ slot = ExecFilterJunk(resultRelInfo->ri_junkFilter, epqslot);
+ tuple = ExecMaterializeSlot(slot);
+ goto lreplace;
+ }
+ else
+ {
+ Datum datum;
+ bool isNull;
+
+ /*
+ * We have a new tuple, but it may not be a
+ * matched-tuple. Since we're performing a right
+ * outer join between the target relation and the
+ * source relation, if the target tuple is updated
+ * such that it no longer satisifies the join
+ * condition, then EvalPlanQual will return the
+ * current source tuple, with target tuple filled
+ * with NULLs.
+ *
+ * We first check if the tuple returned by EPQ has
+ * a valid "ctid" attribute. If ctid is NULL, then
+ * we assume that the join failed to find a
+ * matching row.
+ *
+ * When a valid matching tuple is returned, the
+ * evaluation of MERGE WHEN clauses could be
+ * completely different with this tuple, so
+ * remember this tuple and return for another go.
+ */
+ datum = ExecGetJunkAttribute(epqslot, resultRelInfo->ri_junkFilter->jf_junkAttNo, &isNull);
+ if (isNull)
+ epqstate->epqresult = EPQ_TUPLE_IS_NULL;
+ else
+ {
+ epqstate->epqresult = EPQ_TUPLE_IS_NOT_NULL;
+ /*
+ * Also set the source tuple in the inner slot.
+ * That's where ExecProject expects to see.
+ */
+ econtext->ecxt_innertuple = epqslot;
+ }
+
+ return NULL;
+ }
}
}
+
+ /*
+ * MERGE needs to know the result of any EvalPlanQual.
+ */
+ epqstate->epqresult = EPQ_TUPLE_IS_NULL;
+
/* tuple already deleted; nothing to do */
return NULL;
@@ -1437,7 +1570,7 @@ ExecOnConflictUpdate(ModifyTableState *mtstate,
* there's no historical behavior to break.
*
* It is the user's responsibility to prevent this situation from
- * occurring. These problems are why SQL-2003 similarly specifies
+ * occurring. These problems are why SQL Standard similarly specifies
* that for SQL MERGE, an exception must be raised in the event of
* an attempt to update the same row twice.
*/
@@ -1559,8 +1692,9 @@ ExecOnConflictUpdate(ModifyTableState *mtstate,
/* Execute UPDATE with projection */
*returning = ExecUpdate(mtstate, &tuple.t_self, NULL,
- mtstate->mt_conflproj, planSlot,
+ mtstate->mt_conflproj, planSlot, false,
&mtstate->mt_epqstate, mtstate->ps.state,
+ NULL,
canSetTag);
ReleaseBuffer(buffer);
@@ -1570,6 +1704,9 @@ ExecOnConflictUpdate(ModifyTableState *mtstate,
/*
* Process BEFORE EACH STATEMENT triggers
+ *
+ * The precedent set by ON CONFLICT is that we fire INSERT then UPDATE.
+ * MERGE follows the same logic, firing INSERT, then UPDATE, then DELETE.
*/
static void
fireBSTriggers(ModifyTableState *node)
@@ -1598,6 +1735,14 @@ fireBSTriggers(ModifyTableState *node)
case CMD_DELETE:
ExecBSDeleteTriggers(node->ps.state, resultRelInfo);
break;
+ case CMD_MERGE:
+ if (node->mt_merge_subcommands & ACL_INSERT)
+ ExecBSInsertTriggers(node->ps.state, resultRelInfo);
+ if (node->mt_merge_subcommands & ACL_UPDATE)
+ ExecBSUpdateTriggers(node->ps.state, resultRelInfo);
+ if (node->mt_merge_subcommands & ACL_DELETE)
+ ExecBSDeleteTriggers(node->ps.state, resultRelInfo);
+ break;
default:
elog(ERROR, "unknown operation");
break;
@@ -1628,6 +1773,9 @@ getTargetResultRelInfo(ModifyTableState *node)
/*
* Process AFTER EACH STATEMENT triggers
+ *
+ * The precedent set by ON CONFLICT is that when we have multiple
+ * triggers to fire we do that in reverse order to fireBSTriggers()
*/
static void
fireASTriggers(ModifyTableState *node)
@@ -1652,6 +1800,17 @@ fireASTriggers(ModifyTableState *node)
ExecASDeleteTriggers(node->ps.state, resultRelInfo,
node->mt_transition_capture);
break;
+ case CMD_MERGE:
+ if (node->mt_merge_subcommands & ACL_DELETE)
+ ExecASDeleteTriggers(node->ps.state, resultRelInfo,
+ node->mt_transition_capture);
+ if (node->mt_merge_subcommands & ACL_UPDATE)
+ ExecASUpdateTriggers(node->ps.state, resultRelInfo,
+ node->mt_transition_capture);
+ if (node->mt_merge_subcommands & ACL_INSERT)
+ ExecASInsertTriggers(node->ps.state, resultRelInfo,
+ node->mt_transition_capture);
+ break;
default:
elog(ERROR, "unknown operation");
break;
@@ -1827,6 +1986,443 @@ tupconv_map_for_subplan(ModifyTableState *mtstate, int whichplan)
}
}
+/*
+ * Perform MERGE.
+ */
+static void
+ExecMerge(ModifyTableState *mtstate, EState *estate, TupleTableSlot *slot,
+ JunkFilter *junkfilter, ResultRelInfo *resultRelInfo)
+{
+ ListCell *l;
+ ExprContext *econtext = mtstate->ps.ps_ExprContext;
+ ItemPointer tupleid;
+ ItemPointerData tuple_ctid;
+ HeapTupleData tuple;
+ bool matched = false;
+ Buffer buffer = InvalidBuffer;
+ EPQState *epqstate = &mtstate->mt_epqstate;
+ Oid tableoid = InvalidOid;
+ char relkind;
+ Datum datum;
+ bool isNull;
+ List *mergeActionStateList = NIL;
+ ResultRelInfo *saved_resultRelInfo;
+ int ud_target = 0;
+
+#ifdef MERGE_DEBUG
+ elog(NOTICE, "MERGE row: %s",
+ (!matched ? "not matched" : "matched"));
+#endif
+
+ Assert (junkfilter != NULL);
+
+ relkind = resultRelInfo->ri_RelationDesc->rd_rel->relkind;
+ Assert(relkind == RELKIND_RELATION ||
+ relkind == RELKIND_MATVIEW ||
+ relkind == RELKIND_PARTITIONED_TABLE);
+
+ datum = ExecGetJunkAttribute(slot, junkfilter->jf_junkAttNo, &isNull);
+
+ if (isNull)
+ {
+ matched = false;
+ tupleid = NULL; /* we don't need it for INSERT actions */
+ }
+ else
+ {
+ matched = true; /* Meaningful only for CMD_MERGE */
+ tupleid = (ItemPointer) DatumGetPointer(datum);
+ tuple_ctid = *tupleid; /* be sure we don't free ctid!! */
+ tupleid = &tuple_ctid;
+
+ /*
+ * We always fetch the tableoid while performing MATCHED MERGE action.
+ * This is strictly not required if the target table is not a
+ * partitioned table. But we are not yet optimising for that case.
+ */
+ datum = ExecGetJunkAttribute(slot,
+ junkfilter->jf_otherJunkAttNo,
+ &isNull);
+ Assert(!isNull);
+ tableoid = DatumGetObjectId(datum);
+ }
+
+ /*
+ * If we're dealing with a MATCHED tuple, then tableoid must have been
+ * set correctly. In case of partitioned table, we must now fetch the
+ * correct result relation corresponding to the child table emitting the
+ * matching target row. For normal table, there is just one result relation
+ * and it must be the one emitting the matching row.
+ *
+ * For NOT MATCHED tuple, the only possible action is INSERT. To ensure
+ * that the insert is routed to the correct partition, we must start at the
+ * root partition.
+ */
+ if (OidIsValid(tableoid))
+ {
+ for (ud_target = 0; ud_target < mtstate->mt_nplans; ud_target++)
+ {
+ ResultRelInfo *currRelInfo = mtstate->resultRelInfo + ud_target;
+ Oid relid = RelationGetRelid(currRelInfo->ri_RelationDesc);
+ if (tableoid == relid)
+ break;
+ }
+
+ /* We must have found the child result relation. */
+ Assert(ud_target < mtstate->mt_nplans);
+ resultRelInfo = mtstate->resultRelInfo + ud_target;
+
+ /*
+ * Save the current information and work with the correct result
+ * relation.
+ */
+ saved_resultRelInfo = estate->es_result_relation_info;
+ estate->es_result_relation_info = resultRelInfo;
+
+ /*
+ * And get the correct action lists.
+ */
+ mergeActionStateList = (List *)
+ list_nth(mtstate->mt_mergeActionStateLists, ud_target);
+ }
+ else
+ {
+ /*
+ * We are dealing with NOT MATCHED tuple. For partitioned table, work
+ * with the root partition. For regular tables, just use the currently
+ * active result relation.
+ */
+ resultRelInfo = getTargetResultRelInfo(mtstate);
+ saved_resultRelInfo = estate->es_result_relation_info;
+ estate->es_result_relation_info = resultRelInfo;
+
+ /*
+ * For INSERT actions, any subplan's merge action is OK since the the
+ * INSERT's targetlist and the WHEN conditions can only refer to the
+ * source relation and hence it does not matter which result relation
+ * we work with. So we just choose the first one.
+ */
+ Assert(ud_target == 0);
+ mergeActionStateList = (List *)
+ list_nth(mtstate->mt_mergeActionStateLists, ud_target);
+ }
+
+ /*
+ * Make tuple and any needed join variables available to ExecQual and
+ * ExecProject. The target's existing tuple is installed in the
+ * scantuple. Again, this target relation's slot is required only in
+ * the case of a MATCHED tuple and UPDATE/DELETE actions.
+ */
+ econtext->ecxt_scantuple = mtstate->mt_merge_existing[ud_target];
+ econtext->ecxt_innertuple = slot;
+ econtext->ecxt_outertuple = NULL;
+
+
+ /*
+ * If we find a concurrently updated tuple, some cases require us
+ * to re-evaluate all of the WHEN AND conditions for the new tuple,
+ * so we loop back to here and reset our EvalPlanQual state.
+ */
+lmerge:;
+ epqstate->epqresult = EPQ_UNUSED;
+
+ foreach(l, mergeActionStateList)
+ {
+ MergeActionState *action = (MergeActionState *) lfirst(l);
+
+#ifdef MERGE_DEBUG
+ elog(NOTICE, " action: %s %s",
+ (action->matched ?
+ (action->commandType == CMD_UPDATE ? "UPDATE" : "DELETE") :
+ (action->commandType == CMD_INSERT ? "INSERT" : "DO NOTHING")),
+ (action->matched == matched ? "act " : "skip"));
+#endif
+
+ /*
+ * Apply either MATCHED or NOT MATCHED actions.
+ *
+ * The presence of a NULL value for ctid indicates that
+ * the source query did not match a target row and so at
+ * the time of the snapshot there was no matching row.
+ *
+ * The state of matched or not matched should not change
+ * after the first action is tested, otherwise we would
+ * not have a deterministic outcome, hence why the matched
+ * variable is local and non-modifiable by functions.
+ *
+ * It is valid if no actions are activated, we just do
+ * nothing for that candidate change row and move to next.
+ */
+ if (action->matched != matched)
+ continue;
+
+ /*
+ * For UPDATE/DELETE actions, ensure that the target
+ * tuple is set before we evaluate conditions or
+ * project the resultant tuple.
+ */
+ if (action->commandType == CMD_UPDATE ||
+ action->commandType == CMD_DELETE)
+ {
+ Relation relation = resultRelInfo->ri_RelationDesc;
+
+ /*
+ * UPDATE/DELETE is only invoked for matched rows.
+ * And we must have found the tupleid of the target
+ * row in that case. We fetch using SnapshotAny
+ * because we might get called again after
+ * EvalPlanQual returns us a new tuple. This tuple
+ * may not be visible to our MVCC snapshot.
+ */
+ Assert(matched);
+ Assert(tupleid != NULL);
+
+ tuple.t_self = *tupleid;
+ if (!heap_fetch(relation, SnapshotAny, &tuple,
+ &buffer, true, NULL))
+ elog(ERROR, "Failed to fetch the target tuple");
+
+ /* Store target's existing tuple in the state's dedicated slot */
+ ExecStoreTuple(&tuple, mtstate->mt_merge_existing[ud_target], buffer, false);
+ }
+ else
+ {
+ /*
+ * INSERT/DO_NOTHING actions are only hit when
+ * tuples are not matched.
+ */
+ Assert(!matched);
+ }
+
+ /*
+ * Test condition, if any
+ *
+ * In the absence of a condition we perform the action
+ * unconditionally (no need to check separately since
+ * ExecQual() will return true if there are no
+ * conditions to evaluate).
+ */
+ if (action->whenqual)
+ {
+ int64 startWAL = GetXactWALBytes();
+ bool qual = ExecQual(action->whenqual, econtext);
+
+ /*
+ * SQL Standard says that WHEN AND conditions must not
+ * write to the database, so check we haven't written
+ * any WAL during the test. Very sensible that is, since
+ * we can end up evaluating some tests multiple times if
+ * we have concurrent activity and complex WHEN clauses.
+ *
+ * XXX If we had some clear form of functional labelling
+ * we could use that, if we trusted it.
+ */
+ if (startWAL < GetXactWALBytes())
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("cannot write to database within WHEN AND condition")));
+
+ if (!qual)
+ {
+ if (BufferIsValid(buffer))
+ ReleaseBuffer(buffer);
+ continue;
+ }
+ }
+
+ /*
+ * Check if the existing target tuple meet the USING checks of
+ * UPDATE/DELETE RLS policies. If those checks fail, we throw an
+ * error.
+ *
+ * The way things are structured right now, in case of
+ * concurrent updates, if we decide to retry the update/delete
+ * on the updated version of the tuple, we shall jump back to
+ * lmerge and recheck the updated tuple with the USING quals
+ * again.
+ *
+ * The WITH CHECK quals are applied in ExecUpdate() and hence we
+ * need not do anything special to handle them.
+ *
+ * NOTE: We must do this after WHEN quals are evaluated so that we
+ * check policies only when they matter.
+ */
+ if ((action->commandType == CMD_UPDATE ||
+ action->commandType == CMD_DELETE) && resultRelInfo->ri_WithCheckOptions)
+ {
+ ExecWithCheckOptions(action->commandType == CMD_UPDATE ?
+ WCO_RLS_MERGE_UPDATE_CHECK : WCO_RLS_MERGE_DELETE_CHECK,
+ resultRelInfo,
+ mtstate->mt_merge_existing[ud_target],
+ mtstate->ps.state);
+ }
+
+ /* Perform stated action */
+ switch (action->commandType)
+ {
+ case CMD_INSERT:
+ /*
+ * We set up the projection earlier, so all we
+ * do here is Project, no need for any other
+ * tasks prior to the ExecInsert.
+ */
+ ExecProject(action->proj);
+
+ slot = ExecInsert(mtstate, action->slot, slot,
+ NULL, ONCONFLICT_NONE, estate, action,
+ mtstate->canSetTag);
+ Assert(!BufferIsValid(buffer));
+ break;
+ case CMD_UPDATE:
+ /*
+ * We set up the projection earlier, so all we
+ * do here is Project, no need for any other
+ * tasks prior to the ExecUpdate.
+ */
+ ExecProject(action->proj);
+
+ /*
+ * We don't call ExecFilterJunk() because the
+ * projected tuple using the UPDATE action's
+ * targetlist doesn't have a junk attribute.
+ */
+
+ slot = ExecUpdate(mtstate, tupleid, NULL,
+ action->slot, slot, true,
+ epqstate, estate,
+ action,
+ mtstate->canSetTag);
+ ReleaseBuffer(buffer);
+
+ /*
+ * If we had to use EvalPlanQual to search for updated
+ * tuples then special handling is required...
+ * Note that this handling is identical for both
+ * MERGE UPDATE and MERGE DELETE actions.
+ */
+ if (epqstate->epqresult == EPQ_TUPLE_IS_NOT_NULL)
+ {
+ /*
+ * If EvalPlanQual returns a tuple then we know that we
+ * are still MATCHED, but we don't know which action we
+ * would activate for the new row values in the case that
+ * we have any WHEN MATCHED AND conditions, even if the
+ * current action does not have such a condition.
+ */
+ estate->es_result_relation_info = saved_resultRelInfo;
+ goto lmerge;
+ }
+ /*
+ * If EvalPlanQual did not return a tuple, it means we
+ * have seen a concurrent delete, or a concurrent update
+ * where the row has moved to another partition.
+ *
+ * UPDATE ignores this case and continues.
+ *
+ * If MERGE has a WHEN NOT MATCHED clause we know that the
+ * user would like to INSERT something in this case, yet
+ * we can't see the delete with our snapshot, so take the
+ * safe choice and throw an ERROR. If the user didn't care
+ * about WHEN NOT MATCHED INSERT then neither do we.
+ *
+ * XXX We might consider setting matched = false and loop
+ * back to lmerge though we'd need to do something like
+ * EvalPlanQual, but not quite.
+ */
+ else if (epqstate->epqresult == EPQ_TUPLE_IS_NULL &&
+ mtstate->mt_merge_subcommands & ACL_INSERT)
+ {
+ /*
+ * We need to throw a retryable ERROR because of the
+ * concurrent update which we can't handle.
+ */
+ ereport(ERROR,
+ (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
+ errmsg("could not serialize access due to concurrent update")));
+ }
+
+ /* Count updates */
+ InstrCountFiltered1(&mtstate->ps, 1);
+
+ break;
+ case CMD_DELETE:
+ /* Nothing to Project for a DELETE action */
+ slot = ExecDelete(mtstate, tupleid, NULL,
+ slot, true,
+ epqstate, estate,
+ NULL, false, action,
+ mtstate->canSetTag);
+
+ Assert(BufferIsValid(buffer));
+ ReleaseBuffer(buffer);
+
+ /*
+ * If we had to use EvalPlanQual to search for updated
+ * tuples then special handling is required...
+ * Note that this handling is identical for both
+ * MERGE UPDATE and MERGE DELETE actions.
+ */
+ if (epqstate->epqresult == EPQ_TUPLE_IS_NOT_NULL)
+ {
+ /*
+ * If EvalPlanQual returns a tuple then we know that we
+ * are still MATCHED, but we don't know which action we
+ * would activate for the new row values in the case that
+ * we have any WHEN MATCHED AND conditions, even if the
+ * current action does not have such a condition.
+ */
+ estate->es_result_relation_info = saved_resultRelInfo;
+ goto lmerge;
+ }
+ /*
+ * If EvalPlanQual did not return a tuple, it means we
+ * have seen a concurrent delete, or a concurrent update
+ * where the row has moved to another partition.
+ *
+ * DELETE ignores this case and continues.
+ *
+ * If MERGE has a WHEN NOT MATCHED clause we know that the
+ * user would like to INSERT something in this case, yet
+ * we can't see the delete with our snapshot, so take the
+ * safe choice and throw an ERROR. If the user didn't care
+ * about WHEN NOT MATCHED INSERT then neither do we.
+ *
+ * XXX We might consider setting matched = false and loop
+ * back to lmerge though we'd need to do something like
+ * EvalPlanQual, but not quite.
+ */
+ else if (epqstate->epqresult == EPQ_TUPLE_IS_NULL &&
+ mtstate->mt_merge_subcommands & ACL_INSERT)
+ {
+ /*
+ * We need to throw a retryable ERROR because of the
+ * concurrent update which we can't handle.
+ */
+ ereport(ERROR,
+ (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
+ errmsg("could not serialize access due to concurrent update")));
+ }
+
+ /* Count deletes */
+ InstrCountFiltered2(&mtstate->ps, 1);
+
+ break;
+ case CMD_NOTHING:
+ Assert(!BufferIsValid(buffer));
+ /* Do Nothing */
+ break;
+ default:
+ elog(ERROR, "unknown action in MERGE WHEN clause");
+ }
+
+ /*
+ * We've activated one of the WHEN clauses, so we don't search further.
+ * This is required behaviour, not an optimisation.
+ */
+ estate->es_result_relation_info = saved_resultRelInfo;
+ break;
+ }
+}
/* ----------------------------------------------------------------
* ExecModifyTable
*
@@ -1919,7 +2515,14 @@ ExecModifyTable(PlanState *pstate)
{
/* advance to next subplan if any */
node->mt_whichplan++;
- if (node->mt_whichplan < node->mt_nplans)
+
+ /*
+ * If we are executing MERGE, we only need to execute the first
+ * subplan since it's guranteed to return all the required tuples.
+ * In fact, running remaining subplans would be a problem since we
+ * will end up fethcing the same tuples N times.
+ */
+ if (node->mt_whichplan < node->mt_nplans && (operation != CMD_MERGE))
{
resultRelInfo++;
subplanstate = node->mt_plans[node->mt_whichplan];
@@ -1967,6 +2570,12 @@ ExecModifyTable(PlanState *pstate)
EvalPlanQualSetSlot(&node->mt_epqstate, planSlot);
slot = planSlot;
+ if (operation == CMD_MERGE)
+ {
+ ExecMerge(node, estate, slot, junkfilter, resultRelInfo);
+ continue;
+ }
+
tupleid = NULL;
oldtuple = NULL;
if (junkfilter != NULL)
@@ -1974,7 +2583,9 @@ ExecModifyTable(PlanState *pstate)
/*
* extract the 'ctid' or 'wholerow' junk attribute.
*/
- if (operation == CMD_UPDATE || operation == CMD_DELETE)
+ if (operation == CMD_UPDATE ||
+ operation == CMD_DELETE ||
+ operation == CMD_MERGE)
{
char relkind;
Datum datum;
@@ -2034,9 +2645,12 @@ ExecModifyTable(PlanState *pstate)
}
/*
- * apply the junkfilter if needed.
+ * apply the junkfilter if needed. We don't do this for MERGE
+ * because the action's targetlists do not contain any junk
+ * attributes and the to-be-inserted or updated tuples are
+ * constructed using those targetlists.
*/
- if (operation != CMD_DELETE)
+ if (operation == CMD_UPDATE || operation == CMD_INSERT)
slot = ExecFilterJunk(junkfilter, slot);
}
@@ -2045,16 +2659,16 @@ ExecModifyTable(PlanState *pstate)
case CMD_INSERT:
slot = ExecInsert(node, slot, planSlot,
node->mt_arbiterindexes, node->mt_onconflict,
- estate, node->canSetTag);
+ estate, NULL, node->canSetTag);
break;
case CMD_UPDATE:
- slot = ExecUpdate(node, tupleid, oldtuple, slot, planSlot,
- &node->mt_epqstate, estate, node->canSetTag);
+ slot = ExecUpdate(node, tupleid, oldtuple, slot, planSlot, false,
+ &node->mt_epqstate, estate, NULL, node->canSetTag);
break;
case CMD_DELETE:
- slot = ExecDelete(node, tupleid, oldtuple, planSlot,
+ slot = ExecDelete(node, tupleid, oldtuple, planSlot, false,
&node->mt_epqstate, estate,
- NULL, true, node->canSetTag);
+ NULL, true, NULL, node->canSetTag);
break;
default:
elog(ERROR, "unknown operation");
@@ -2125,6 +2739,9 @@ ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags)
mtstate->mt_plans = (PlanState **) palloc0(sizeof(PlanState *) * nplans);
mtstate->resultRelInfo = estate->es_result_relations + node->resultRelIndex;
+ mtstate->mt_merge_existing = (TupleTableSlot **)
+ palloc0(sizeof (TupleTableSlot *) * nplans);
+
/* If modifying a partitioned table, initialize the root table info */
if (node->rootResultRelIndex >= 0)
mtstate->rootResultRelInfo = estate->es_root_result_relations +
@@ -2206,6 +2823,14 @@ ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags)
eflags);
}
+ /*
+ * Setup MERGE target table RTI, if needed.
+ */
+ if (operation == CMD_MERGE)
+ {
+ resultRelInfo->ri_mergeTargetRTI =
+ list_nth_int(node->mergeTargetRelations, i);
+ }
resultRelInfo++;
i++;
}
@@ -2227,7 +2852,8 @@ ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags)
* partition key.
*/
if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE &&
- (operation == CMD_INSERT || update_tuple_routing_needed))
+ (operation == CMD_INSERT || operation == CMD_MERGE ||
+ update_tuple_routing_needed))
{
proute = mtstate->mt_partition_tuple_routing =
ExecSetupPartitionTupleRouting(mtstate,
@@ -2521,6 +3147,93 @@ ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags)
}
}
+ /*
+ * Initialize everything for CMD_MERGE
+ */
+ mtstate->mt_mergeActionStateLists = NIL;
+ resultRelInfo = mtstate->resultRelInfo;
+
+ if (node->mergeActionLists)
+ {
+ ListCell *l;
+ ExprContext *econtext;
+
+ mtstate->mt_merge_subcommands = 0;
+
+ if (mtstate->ps.ps_ExprContext == NULL)
+ ExecAssignExprContext(estate, &mtstate->ps);
+
+ econtext = mtstate->ps.ps_ExprContext;
+
+ /*
+ * Create a MergeActionState for each action on the mergeActionList
+ */
+ foreach(l, node->mergeActionLists)
+ {
+ List *mergeActionList = (List *) lfirst(l);
+ List *mergeActionStateList = NIL;
+ ListCell *l2;
+ int whichplan = resultRelInfo - mtstate->resultRelInfo;
+
+ /* initialize slot for the existing tuple */
+ mtstate->mt_merge_existing[whichplan] = ExecInitExtraTupleSlot(mtstate->ps.state);
+ ExecSetSlotDescriptor(mtstate->mt_merge_existing[whichplan],
+ resultRelInfo->ri_RelationDesc->rd_att);
+
+ foreach (l2, mergeActionList)
+ {
+ MergeAction *action = (MergeAction *) lfirst(l2);
+ MergeActionState *action_state = makeNode(MergeActionState);
+ TupleDesc tupDesc;
+
+ action_state->matched = action->matched;
+ action_state->commandType = action->commandType;
+ action_state->whenqual = ExecInitQual((List *) action->qual,
+ &mtstate->ps);
+
+ /* create target slot for this action's projection */
+ tupDesc = ExecTypeFromTL((List *) action->targetList,
+ resultRelInfo->ri_RelationDesc->rd_rel->relhasoids);
+ action_state->slot = ExecInitExtraTupleSlot(mtstate->ps.state);
+ ExecSetSlotDescriptor(action_state->slot, tupDesc);
+
+ /* build action projection state */
+ action_state->proj =
+ ExecBuildProjectionInfo(action->targetList, econtext,
+ action_state->slot, &mtstate->ps,
+ resultRelInfo->ri_RelationDesc->rd_att);
+
+ mergeActionStateList = lappend(mergeActionStateList,
+ action_state);
+ /*
+ * XXX if we support transition tables this would need to move earlier
+ * before ExecSetupTransitionCaptureState()
+ */
+ switch (action->commandType)
+ {
+ case CMD_INSERT:
+ mtstate->mt_merge_subcommands |= ACL_INSERT;
+ break;
+ case CMD_UPDATE:
+ mtstate->mt_merge_subcommands |= ACL_UPDATE;
+ break;
+ case CMD_DELETE:
+ mtstate->mt_merge_subcommands |= ACL_DELETE;
+ break;
+ case CMD_NOTHING:
+ break;
+ default:
+ elog(ERROR, "unknown operation");
+ break;
+ }
+ }
+
+ mtstate->mt_mergeActionStateLists = lappend(mtstate->mt_mergeActionStateLists,
+ mergeActionStateList);
+ resultRelInfo++;
+ }
+ }
+
/* select first subplan */
mtstate->mt_whichplan = 0;
subplan = (Plan *) linitial(node->plans);
@@ -2534,7 +3247,7 @@ ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags)
* --- no need to look first. Typically, this will be a 'ctid' or
* 'wholerow' attribute, but in the case of a foreign data wrapper it
* might be a set of junk attributes sufficient to identify the remote
- * row.
+ * row. We follow this logic for MERGE, so it always has a junk 'ctid'.
*
* If there are multiple result relations, each one needs its own junk
* filter. Note multiple rels are only possible for UPDATE/DELETE, so we
@@ -2562,6 +3275,7 @@ ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags)
break;
case CMD_UPDATE:
case CMD_DELETE:
+ case CMD_MERGE:
junk_filter_needed = true;
break;
default:
@@ -2577,6 +3291,7 @@ ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags)
JunkFilter *j;
subplan = mtstate->mt_plans[i]->plan;
+ /* XXX we probably need to check plan output for CMD_MERGE also */
if (operation == CMD_INSERT || operation == CMD_UPDATE)
ExecCheckPlanOutput(resultRelInfo->ri_RelationDesc,
subplan->targetlist);
@@ -2585,7 +3300,9 @@ ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags)
resultRelInfo->ri_RelationDesc->rd_att->tdhasoid,
ExecInitExtraTupleSlot(estate));
- if (operation == CMD_UPDATE || operation == CMD_DELETE)
+ if (operation == CMD_UPDATE ||
+ operation == CMD_DELETE ||
+ operation == CMD_MERGE)
{
/* For UPDATE/DELETE, find the appropriate junk attr now */
char relkind;
@@ -2598,6 +3315,14 @@ ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags)
j->jf_junkAttNo = ExecFindJunkAttribute(j, "ctid");
if (!AttributeNumberIsValid(j->jf_junkAttNo))
elog(ERROR, "could not find junk ctid column");
+
+ if (operation == CMD_MERGE)
+ {
+ j->jf_otherJunkAttNo = ExecFindJunkAttribute(j, "tableoid");
+ if (!AttributeNumberIsValid(j->jf_otherJunkAttNo))
+ elog(ERROR, "could not find junk tableoid column");
+
+ }
}
else if (relkind == RELKIND_FOREIGN_TABLE)
{
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 9fc4431..e050a31 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -2404,6 +2404,9 @@ _SPI_pquery(QueryDesc *queryDesc, bool fire_triggers, uint64 tcount)
else
res = SPI_OK_UPDATE;
break;
+ case CMD_MERGE:
+ res = SPI_OK_MERGE;
+ break;
default:
return SPI_ERROR_OPUNKNOWN;
}
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index 82255b0..86d463b 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -206,6 +206,7 @@ _copyModifyTable(const ModifyTable *from)
COPY_NODE_FIELD(partitioned_rels);
COPY_SCALAR_FIELD(partColsUpdated);
COPY_NODE_FIELD(resultRelations);
+ COPY_NODE_FIELD(mergeTargetRelations);
COPY_SCALAR_FIELD(resultRelIndex);
COPY_SCALAR_FIELD(rootResultRelIndex);
COPY_NODE_FIELD(plans);
@@ -221,6 +222,8 @@ _copyModifyTable(const ModifyTable *from)
COPY_NODE_FIELD(onConflictWhere);
COPY_SCALAR_FIELD(exclRelRTI);
COPY_NODE_FIELD(exclRelTlist);
+ COPY_NODE_FIELD(mergeSourceTargetLists);
+ COPY_NODE_FIELD(mergeActionLists);
return newnode;
}
@@ -2976,6 +2979,9 @@ _copyQuery(const Query *from)
COPY_NODE_FIELD(setOperations);
COPY_NODE_FIELD(constraintDeps);
COPY_NODE_FIELD(withCheckOptions);
+ COPY_SCALAR_FIELD(mergeTarget_relation);
+ COPY_NODE_FIELD(mergeSourceTargetList);
+ COPY_NODE_FIELD(mergeActionList);
COPY_LOCATION_FIELD(stmt_location);
COPY_LOCATION_FIELD(stmt_len);
@@ -3039,6 +3045,34 @@ _copyUpdateStmt(const UpdateStmt *from)
return newnode;
}
+static MergeStmt *
+_copyMergeStmt(const MergeStmt *from)
+{
+ MergeStmt *newnode = makeNode(MergeStmt);
+
+ COPY_NODE_FIELD(relation);
+ COPY_NODE_FIELD(source_relation);
+ COPY_NODE_FIELD(join_condition);
+ COPY_NODE_FIELD(mergeActionList);
+
+ return newnode;
+}
+
+static MergeAction *
+_copyMergeAction(const MergeAction *from)
+{
+ MergeAction *newnode = makeNode(MergeAction);
+
+ COPY_SCALAR_FIELD(matched);
+ COPY_SCALAR_FIELD(commandType);
+ COPY_NODE_FIELD(condition);
+ COPY_NODE_FIELD(qual);
+ COPY_NODE_FIELD(stmt);
+ COPY_NODE_FIELD(targetList);
+
+ return newnode;
+}
+
static SelectStmt *
_copySelectStmt(const SelectStmt *from)
{
@@ -5098,6 +5132,12 @@ copyObjectImpl(const void *from)
case T_UpdateStmt:
retval = _copyUpdateStmt(from);
break;
+ case T_MergeStmt:
+ retval = _copyMergeStmt(from);
+ break;
+ case T_MergeAction:
+ retval = _copyMergeAction(from);
+ break;
case T_SelectStmt:
retval = _copySelectStmt(from);
break;
diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c
index b9bc8e3..0877f5a 100644
--- a/src/backend/nodes/equalfuncs.c
+++ b/src/backend/nodes/equalfuncs.c
@@ -987,6 +987,8 @@ _equalQuery(const Query *a, const Query *b)
COMPARE_NODE_FIELD(setOperations);
COMPARE_NODE_FIELD(constraintDeps);
COMPARE_NODE_FIELD(withCheckOptions);
+ COMPARE_NODE_FIELD(mergeSourceTargetList);
+ COMPARE_NODE_FIELD(mergeActionList);
COMPARE_LOCATION_FIELD(stmt_location);
COMPARE_LOCATION_FIELD(stmt_len);
@@ -1043,6 +1045,30 @@ _equalUpdateStmt(const UpdateStmt *a, const UpdateStmt *b)
}
static bool
+_equalMergeStmt(const MergeStmt *a, const MergeStmt *b)
+{
+ COMPARE_NODE_FIELD(relation);
+ COMPARE_NODE_FIELD(source_relation);
+ COMPARE_NODE_FIELD(join_condition);
+ COMPARE_NODE_FIELD(mergeActionList);
+
+ return true;
+}
+
+static bool
+_equalMergeAction(const MergeAction *a, const MergeAction *b)
+{
+ COMPARE_SCALAR_FIELD(matched);
+ COMPARE_SCALAR_FIELD(commandType);
+ COMPARE_NODE_FIELD(condition);
+ COMPARE_NODE_FIELD(qual);
+ COMPARE_NODE_FIELD(stmt);
+ COMPARE_NODE_FIELD(targetList);
+
+ return true;
+}
+
+static bool
_equalSelectStmt(const SelectStmt *a, const SelectStmt *b)
{
COMPARE_NODE_FIELD(distinctClause);
@@ -3230,6 +3256,12 @@ equal(const void *a, const void *b)
case T_UpdateStmt:
retval = _equalUpdateStmt(a, b);
break;
+ case T_MergeStmt:
+ retval = _equalMergeStmt(a, b);
+ break;
+ case T_MergeAction:
+ retval = _equalMergeAction(a, b);
+ break;
case T_SelectStmt:
retval = _equalSelectStmt(a, b);
break;
diff --git a/src/backend/nodes/nodeFuncs.c b/src/backend/nodes/nodeFuncs.c
index 6c76c41..a631805 100644
--- a/src/backend/nodes/nodeFuncs.c
+++ b/src/backend/nodes/nodeFuncs.c
@@ -2146,6 +2146,16 @@ expression_tree_walker(Node *node,
return true;
}
break;
+ case T_MergeAction:
+ {
+ MergeAction *action = (MergeAction *) node;
+
+ if (walker(action->targetList, context))
+ return true;
+ if (walker(action->qual, context))
+ return true;
+ }
+ break;
case T_JoinExpr:
{
JoinExpr *join = (JoinExpr *) node;
@@ -2255,6 +2265,10 @@ query_tree_walker(Query *query,
return true;
if (walker((Node *) query->onConflict, context))
return true;
+ if (walker((Node *) query->mergeSourceTargetList, context))
+ return true;
+ if (walker((Node *) query->mergeActionList, context))
+ return true;
if (walker((Node *) query->returningList, context))
return true;
if (walker((Node *) query->jointree, context))
@@ -2932,6 +2946,18 @@ expression_tree_mutator(Node *node,
return (Node *) newnode;
}
break;
+ case T_MergeAction:
+ {
+ MergeAction *action = (MergeAction *) node;
+ MergeAction *newnode;
+
+ FLATCOPY(newnode, action, MergeAction);
+ MUTATE(newnode->qual, action->qual, Node *);
+ MUTATE(newnode->targetList, action->targetList, List *);
+
+ return (Node *) newnode;
+ }
+ break;
case T_JoinExpr:
{
JoinExpr *join = (JoinExpr *) node;
@@ -3083,6 +3109,8 @@ query_tree_mutator(Query *query,
MUTATE(query->targetList, query->targetList, List *);
MUTATE(query->withCheckOptions, query->withCheckOptions, List *);
MUTATE(query->onConflict, query->onConflict, OnConflictExpr *);
+ MUTATE(query->mergeSourceTargetList, query->mergeSourceTargetList, List *);
+ MUTATE(query->mergeActionList, query->mergeActionList, List *);
MUTATE(query->returningList, query->returningList, List *);
MUTATE(query->jointree, query->jointree, FromExpr *);
MUTATE(query->setOperations, query->setOperations, Node *);
@@ -3224,9 +3252,9 @@ query_or_expression_tree_mutator(Node *node,
* boundaries: we descend to everything that's possibly interesting.
*
* Currently, the node type coverage here extends only to DML statements
- * (SELECT/INSERT/UPDATE/DELETE) and nodes that can appear in them, because
- * this is used mainly during analysis of CTEs, and only DML statements can
- * appear in CTEs.
+ * (SELECT/INSERT/UPDATE/DELETE/MERGE) and nodes that can appear in them,
+ * because this is used mainly during analysis of CTEs, and only DML
+ * statements can appear in CTEs.
*/
bool
raw_expression_tree_walker(Node *node,
@@ -3406,6 +3434,20 @@ raw_expression_tree_walker(Node *node,
return true;
}
break;
+ case T_MergeStmt:
+ {
+ MergeStmt *stmt = (MergeStmt *) node;
+
+ if (walker(stmt->relation, context))
+ return true;
+ if (walker(stmt->source_relation, context))
+ return true;
+ if (walker(stmt->join_condition, context))
+ return true;
+ if (walker(stmt->mergeActionList, context))
+ return true;
+ }
+ break;
case T_SelectStmt:
{
SelectStmt *stmt = (SelectStmt *) node;
diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index 011d2a3..343ea03 100644
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -374,6 +374,7 @@ _outModifyTable(StringInfo str, const ModifyTable *node)
WRITE_NODE_FIELD(partitioned_rels);
WRITE_BOOL_FIELD(partColsUpdated);
WRITE_NODE_FIELD(resultRelations);
+ WRITE_NODE_FIELD(mergeTargetRelations);
WRITE_INT_FIELD(resultRelIndex);
WRITE_INT_FIELD(rootResultRelIndex);
WRITE_NODE_FIELD(plans);
@@ -389,6 +390,21 @@ _outModifyTable(StringInfo str, const ModifyTable *node)
WRITE_NODE_FIELD(onConflictWhere);
WRITE_UINT_FIELD(exclRelRTI);
WRITE_NODE_FIELD(exclRelTlist);
+ WRITE_NODE_FIELD(mergeSourceTargetLists);
+ WRITE_NODE_FIELD(mergeActionLists);
+}
+
+static void
+_outMergeAction(StringInfo str, const MergeAction *node)
+{
+ WRITE_NODE_TYPE("MERGEACTION");
+
+ WRITE_BOOL_FIELD(matched);
+ WRITE_ENUM_FIELD(commandType, CmdType);
+ WRITE_NODE_FIELD(condition);
+ WRITE_NODE_FIELD(qual);
+ /* We don't dump the stmt node */
+ WRITE_NODE_FIELD(targetList);
}
static void
@@ -2113,6 +2129,7 @@ _outModifyTablePath(StringInfo str, const ModifyTablePath *node)
WRITE_NODE_FIELD(partitioned_rels);
WRITE_BOOL_FIELD(partColsUpdated);
WRITE_NODE_FIELD(resultRelations);
+ WRITE_NODE_FIELD(mergeTargetRelations);
WRITE_NODE_FIELD(subpaths);
WRITE_NODE_FIELD(subroots);
WRITE_NODE_FIELD(withCheckOptionLists);
@@ -2120,6 +2137,8 @@ _outModifyTablePath(StringInfo str, const ModifyTablePath *node)
WRITE_NODE_FIELD(rowMarks);
WRITE_NODE_FIELD(onconflict);
WRITE_INT_FIELD(epqParam);
+ WRITE_NODE_FIELD(mergeSourceTargetLists);
+ WRITE_NODE_FIELD(mergeActionLists);
}
static void
@@ -2940,6 +2959,9 @@ _outQuery(StringInfo str, const Query *node)
WRITE_NODE_FIELD(setOperations);
WRITE_NODE_FIELD(constraintDeps);
/* withCheckOptions intentionally omitted, see comment in parsenodes.h */
+ WRITE_INT_FIELD(mergeTarget_relation);
+ WRITE_NODE_FIELD(mergeSourceTargetList);
+ WRITE_NODE_FIELD(mergeActionList);
WRITE_LOCATION_FIELD(stmt_location);
WRITE_LOCATION_FIELD(stmt_len);
}
@@ -3655,6 +3677,9 @@ outNode(StringInfo str, const void *obj)
case T_ModifyTable:
_outModifyTable(str, obj);
break;
+ case T_MergeAction:
+ _outMergeAction(str, obj);
+ break;
case T_Append:
_outAppend(str, obj);
break;
diff --git a/src/backend/nodes/readfuncs.c b/src/backend/nodes/readfuncs.c
index 068db35..cdbf48e 100644
--- a/src/backend/nodes/readfuncs.c
+++ b/src/backend/nodes/readfuncs.c
@@ -270,6 +270,9 @@ _readQuery(void)
READ_NODE_FIELD(setOperations);
READ_NODE_FIELD(constraintDeps);
/* withCheckOptions intentionally omitted, see comment in parsenodes.h */
+ READ_INT_FIELD(mergeTarget_relation);
+ READ_NODE_FIELD(mergeSourceTargetList);
+ READ_NODE_FIELD(mergeActionList);
READ_LOCATION_FIELD(stmt_location);
READ_LOCATION_FIELD(stmt_len);
@@ -1575,6 +1578,7 @@ _readModifyTable(void)
READ_NODE_FIELD(partitioned_rels);
READ_BOOL_FIELD(partColsUpdated);
READ_NODE_FIELD(resultRelations);
+ READ_NODE_FIELD(mergeTargetRelations);
READ_INT_FIELD(resultRelIndex);
READ_INT_FIELD(rootResultRelIndex);
READ_NODE_FIELD(plans);
@@ -1590,6 +1594,8 @@ _readModifyTable(void)
READ_NODE_FIELD(onConflictWhere);
READ_UINT_FIELD(exclRelRTI);
READ_NODE_FIELD(exclRelTlist);
+ READ_NODE_FIELD(mergeSourceTargetLists);
+ READ_NODE_FIELD(mergeActionLists);
READ_DONE();
}
diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c
index da0cc7f..84f303f 100644
--- a/src/backend/optimizer/plan/createplan.c
+++ b/src/backend/optimizer/plan/createplan.c
@@ -282,9 +282,13 @@ static ModifyTable *make_modifytable(PlannerInfo *root,
CmdType operation, bool canSetTag,
Index nominalRelation, List *partitioned_rels,
bool partColsUpdated,
- List *resultRelations, List *subplans,
+ List *resultRelations,
+ List *mergeTargetRelations,
+ List *subplans,
List *withCheckOptionLists, List *returningLists,
- List *rowMarks, OnConflictExpr *onconflict, int epqParam);
+ List *rowMarks, OnConflictExpr *onconflict,
+ List *mergeSourceTargetList,
+ List *mergeActionList, int epqParam);
static GatherMerge *create_gather_merge_plan(PlannerInfo *root,
GatherMergePath *best_path);
@@ -2386,11 +2390,14 @@ create_modifytable_plan(PlannerInfo *root, ModifyTablePath *best_path)
best_path->partitioned_rels,
best_path->partColsUpdated,
best_path->resultRelations,
+ best_path->mergeTargetRelations,
subplans,
best_path->withCheckOptionLists,
best_path->returningLists,
best_path->rowMarks,
best_path->onconflict,
+ best_path->mergeSourceTargetLists,
+ best_path->mergeActionLists,
best_path->epqParam);
copy_generic_path_info(&plan->plan, &best_path->path);
@@ -6462,9 +6469,13 @@ make_modifytable(PlannerInfo *root,
CmdType operation, bool canSetTag,
Index nominalRelation, List *partitioned_rels,
bool partColsUpdated,
- List *resultRelations, List *subplans,
+ List *resultRelations,
+ List *mergeTargetRelations,
+ List *subplans,
List *withCheckOptionLists, List *returningLists,
- List *rowMarks, OnConflictExpr *onconflict, int epqParam)
+ List *rowMarks, OnConflictExpr *onconflict,
+ List *mergeSourceTargetLists,
+ List *mergeActionLists, int epqParam)
{
ModifyTable *node = makeNode(ModifyTable);
List *fdw_private_list;
@@ -6477,6 +6488,12 @@ make_modifytable(PlannerInfo *root,
list_length(resultRelations) == list_length(withCheckOptionLists));
Assert(returningLists == NIL ||
list_length(resultRelations) == list_length(returningLists));
+ Assert(mergeActionLists == NIL ||
+ list_length(resultRelations) == list_length(mergeActionLists));
+ Assert(mergeSourceTargetLists == NIL ||
+ list_length(resultRelations) == list_length(mergeSourceTargetLists));
+ Assert(mergeActionLists == NIL ||
+ list_length(resultRelations) == list_length(mergeTargetRelations));
node->plan.lefttree = NULL;
node->plan.righttree = NULL;
@@ -6490,6 +6507,7 @@ make_modifytable(PlannerInfo *root,
node->partitioned_rels = partitioned_rels;
node->partColsUpdated = partColsUpdated;
node->resultRelations = resultRelations;
+ node->mergeTargetRelations = mergeTargetRelations;
node->resultRelIndex = -1; /* will be set correctly in setrefs.c */
node->rootResultRelIndex = -1; /* will be set correctly in setrefs.c */
node->plans = subplans;
@@ -6522,6 +6540,8 @@ make_modifytable(PlannerInfo *root,
node->withCheckOptionLists = withCheckOptionLists;
node->returningLists = returningLists;
node->rowMarks = rowMarks;
+ node->mergeSourceTargetLists = mergeSourceTargetLists;
+ node->mergeActionLists = mergeActionLists;
node->epqParam = epqParam;
/*
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
index 3e8cd14..be5184e 100644
--- a/src/backend/optimizer/plan/planner.c
+++ b/src/backend/optimizer/plan/planner.c
@@ -205,6 +205,7 @@ static void add_partial_paths_to_grouping_rel(PlannerInfo *root,
List *havingQual);
static bool can_parallel_agg(PlannerInfo *root, RelOptInfo *input_rel,
RelOptInfo *grouped_rel, const AggClauseCosts *agg_costs);
+static Index find_mergetarget_for_rel(PlannerInfo *root, Index child_relid);
/*****************************************************************************
@@ -737,6 +738,24 @@ subquery_planner(PlannerGlobal *glob, Query *parse,
/* exclRelTlist contains only Vars, so no preprocessing needed */
}
+ foreach (l, parse->mergeActionList)
+ {
+ MergeAction *action = (MergeAction *) lfirst(l);
+
+ action->targetList = (List *)
+ preprocess_expression(root,
+ (Node *) action->targetList,
+ EXPRKIND_TARGET);
+ action->qual =
+ preprocess_expression(root,
+ (Node *) action->qual,
+ EXPRKIND_QUAL);
+ }
+
+ parse->mergeSourceTargetList = (List *)
+ preprocess_expression(root, (Node *) parse->mergeSourceTargetList,
+ EXPRKIND_TARGET);
+
root->append_rel_list = (List *)
preprocess_expression(root, (Node *) root->append_rel_list,
EXPRKIND_APPINFO);
@@ -1109,9 +1128,13 @@ inheritance_planner(PlannerInfo *root)
List *subpaths = NIL;
List *subroots = NIL;
List *resultRelations = NIL;
+ List *mergeTargetRelations = NIL;
+ Index mergeTargetRelation;
List *withCheckOptionLists = NIL;
List *returningLists = NIL;
List *rowMarks;
+ List *mergeActionLists = NIL;
+ List *mergeSourceTargetLists = NIL;
RelOptInfo *final_rel;
ListCell *lc;
Index rti;
@@ -1469,6 +1492,16 @@ inheritance_planner(PlannerInfo *root)
/* Build list of target-relation RT indexes */
resultRelations = lappend_int(resultRelations, appinfo->child_relid);
+ /* Build list of merge target-relation RT indexes */
+ if (parse->commandType == CMD_MERGE)
+ {
+ mergeTargetRelation = find_mergetarget_for_rel(root,
+ appinfo->child_relid);
+ Assert(mergeTargetRelation > 0);
+ mergeTargetRelations = lappend_int(mergeTargetRelations,
+ mergeTargetRelation);
+ }
+
/* Build lists of per-relation WCO and RETURNING targetlists */
if (parse->withCheckOptions)
withCheckOptionLists = lappend(withCheckOptionLists,
@@ -1477,6 +1510,12 @@ inheritance_planner(PlannerInfo *root)
returningLists = lappend(returningLists,
subroot->parse->returningList);
+ if (parse->mergeActionList)
+ mergeActionLists = lappend(mergeActionLists,
+ subroot->parse->mergeActionList);
+ if (parse->mergeSourceTargetList)
+ mergeSourceTargetLists = lappend(mergeSourceTargetLists,
+ subroot->parse->mergeSourceTargetList);
Assert(!parse->onConflict);
}
@@ -1536,12 +1575,15 @@ inheritance_planner(PlannerInfo *root)
partitioned_rels,
partColsUpdated,
resultRelations,
+ mergeTargetRelations,
subpaths,
subroots,
withCheckOptionLists,
returningLists,
rowMarks,
NULL,
+ mergeSourceTargetLists,
+ mergeActionLists,
SS_assign_special_param(root)));
}
@@ -2107,8 +2149,8 @@ grouping_planner(PlannerInfo *root, bool inheritance_update,
}
/*
- * If this is an INSERT/UPDATE/DELETE, and we're not being called from
- * inheritance_planner, add the ModifyTable node.
+ * If this is an INSERT/UPDATE/DELETE/MERGE, and we're not being called
+ * from inheritance_planner, add the ModifyTable node.
*/
if (parse->commandType != CMD_SELECT && !inheritance_update)
{
@@ -2148,12 +2190,15 @@ grouping_planner(PlannerInfo *root, bool inheritance_update,
NIL,
false,
list_make1_int(parse->resultRelation),
+ list_make1_int(parse->mergeTarget_relation),
list_make1(path),
list_make1(root),
withCheckOptionLists,
returningLists,
rowMarks,
parse->onConflict,
+ list_make1(parse->mergeSourceTargetList),
+ list_make1(parse->mergeActionList),
SS_assign_special_param(root));
}
@@ -6435,3 +6480,29 @@ can_parallel_agg(PlannerInfo *root, RelOptInfo *input_rel,
/* Everything looks good. */
return true;
}
+
+static Index
+find_mergetarget_for_rel(PlannerInfo *root, Index child_relid)
+{
+ Query *parse = root->parse;
+ Index mergeTarget_relation = parse->mergeTarget_relation;
+ RangeTblEntry *rte, *child_rte;
+ ListCell *l;
+
+ rte = rt_fetch(child_relid, parse->rtable);
+
+ foreach (l, root->append_rel_list)
+ {
+ AppendRelInfo *appinfo = (AppendRelInfo *) lfirst(l);
+
+ if (appinfo->parent_relid != mergeTarget_relation)
+ continue;
+
+ child_rte = rt_fetch(appinfo->child_relid, parse->rtable);
+ if (child_rte->relid == rte->relid)
+ return appinfo->child_relid;
+ }
+
+ return 0;
+}
+
diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c
index 4617d12..c7f601a 100644
--- a/src/backend/optimizer/plan/setrefs.c
+++ b/src/backend/optimizer/plan/setrefs.c
@@ -851,6 +851,68 @@ set_plan_refs(PlannerInfo *root, Plan *plan, int rtoffset)
fix_scan_list(root, splan->exclRelTlist, rtoffset);
}
+ /*
+ * The MERGE produces the target rows by performing a right
+ * join between the target relation and the source relation
+ * (which could be a plain relation or a subquery). The INSERT
+ * and UPDATE actions of the MERGE requires access to the
+ * columns from the source relation. We arrange things so that
+ * the source relation attributes are available as INNER_VAR
+ * and the target relation attributes are available from the
+ * scan tuple.
+ */
+ if (splan->mergeActionLists != NIL)
+ {
+ ListCell *l2, *l3, *l4;
+
+ /*
+ * mergeSourceTargetList is already setup correctly to
+ * include all Vars coming from the source relation. So we
+ * fix the targetList of individual action nodes by
+ * ensuring that the source relation Vars are referenced as
+ * INNER_VAR. Note that for this to work correctly, during
+ * execution, the ecxt_innertuple must be set to the tuple
+ * obtained from the source relation.
+ *
+ * We leave the Vars from the result relation (i.e. the
+ * target relation) unchanged i.e. those Vars would be
+ * picked from the scan slot. So during execution, we must
+ * ensure that ecxt_scantuple is setup correctly to refer
+ * to the tuple from the target relation.
+ */
+
+ forthree(l2, splan->mergeActionLists,
+ l3, splan->resultRelations,
+ l4, splan->mergeSourceTargetLists)
+ {
+ List *mergeActionList = (List *)lfirst(l2);
+ int resultRelIndex = lfirst_int(l3);
+ List *mergeSourceTargetList = (List *)lfirst(l4);
+ indexed_tlist *itlist;
+
+ itlist = build_tlist_index(mergeSourceTargetList);
+
+ foreach (l, mergeActionList)
+ {
+ MergeAction *action = (MergeAction *) lfirst(l);
+
+ /* Fix targetList of each action. */
+ action->targetList = fix_join_expr(root,
+ action->targetList,
+ NULL, itlist,
+ resultRelIndex,
+ rtoffset);
+
+ /* Fix quals too. */
+ action->qual = (Node *) fix_join_expr(root,
+ (List *) action->qual,
+ NULL, itlist,
+ resultRelIndex,
+ rtoffset);
+ }
+ }
+ }
+
splan->nominalRelation += rtoffset;
splan->exclRelRTI += rtoffset;
diff --git a/src/backend/optimizer/prep/preptlist.c b/src/backend/optimizer/prep/preptlist.c
index 8603fee..872cfeb 100644
--- a/src/backend/optimizer/prep/preptlist.c
+++ b/src/backend/optimizer/prep/preptlist.c
@@ -105,9 +105,13 @@ preprocess_targetlist(PlannerInfo *root)
* scribbles on parse->targetList, which is not very desirable, but we
* keep it that way to avoid changing APIs used by FDWs.
*/
- if (command_type == CMD_UPDATE || command_type == CMD_DELETE)
+ if (command_type == CMD_UPDATE ||
+ command_type == CMD_DELETE)
rewriteTargetListUD(parse, target_rte, target_relation);
+ if (command_type == CMD_MERGE)
+ rewriteTargetListMerge(parse, target_relation);
+
/*
* for heap_form_tuple to work, the targetlist must match the exact order
* of the attributes. We also need to fill in any missing attributes. -ay
@@ -119,6 +123,38 @@ preprocess_targetlist(PlannerInfo *root)
result_relation, target_relation);
/*
+ * For MERGE command, handle targetlist of each MergeAction separately. We
+ * give the same treatment to MergeAction->targetList as we would have
+ * given to a regular INSERT/UPDATE/DELETE.
+ */
+ if (command_type == CMD_MERGE)
+ {
+ ListCell *l;
+
+ foreach(l, parse->mergeActionList)
+ {
+ MergeAction *action = (MergeAction *) lfirst(l);
+
+ switch (action->commandType)
+ {
+ case CMD_INSERT:
+ case CMD_UPDATE:
+ action->targetList = expand_targetlist(action->targetList,
+ action->commandType,
+ result_relation, target_relation);
+ break;
+ case CMD_DELETE:
+ break;
+ case CMD_NOTHING:
+ break;
+ default:
+ elog(ERROR, "unknown action in MERGE WHEN clause");
+
+ }
+ }
+ }
+
+ /*
* Add necessary junk columns for rowmarked rels. These values are needed
* for locking of rels selected FOR UPDATE/SHARE, and to do EvalPlanQual
* rechecking. See comments for PlanRowMark in plannodes.h.
@@ -348,6 +384,7 @@ expand_targetlist(List *tlist, int command_type,
true /* byval */ );
}
break;
+ case CMD_MERGE:
case CMD_UPDATE:
if (!att_tup->attisdropped)
{
diff --git a/src/backend/optimizer/prep/prepunion.c b/src/backend/optimizer/prep/prepunion.c
index b586f94..41e813b 100644
--- a/src/backend/optimizer/prep/prepunion.c
+++ b/src/backend/optimizer/prep/prepunion.c
@@ -1991,7 +1991,24 @@ adjust_appendrel_attrs(PlannerInfo *root, Node *node, int nappinfos,
if (newnode->commandType == CMD_UPDATE)
newnode->targetList =
adjust_inherited_tlist(newnode->targetList,
- appinfo);
+ appinfo);
+
+ /*
+ * Fix resnos in the MergeAction's tlist, if the action is an
+ * UPDATE action.
+ */
+ if (newnode->commandType == CMD_MERGE)
+ {
+ ListCell *l;
+ foreach (l, newnode->mergeActionList)
+ {
+ MergeAction *action = (MergeAction *) lfirst(l);
+ if (action->commandType == CMD_UPDATE)
+ action->targetList =
+ adjust_inherited_tlist(action->targetList,
+ appinfo);
+ }
+ }
break;
}
}
diff --git a/src/backend/optimizer/util/pathnode.c b/src/backend/optimizer/util/pathnode.c
index fe3b458..e3fe95a 100644
--- a/src/backend/optimizer/util/pathnode.c
+++ b/src/backend/optimizer/util/pathnode.c
@@ -3284,17 +3284,21 @@ create_lockrows_path(PlannerInfo *root, RelOptInfo *rel,
* 'rowMarks' is a list of PlanRowMarks (non-locking only)
* 'onconflict' is the ON CONFLICT clause, or NULL
* 'epqParam' is the ID of Param for EvalPlanQual re-eval
+ * 'mergeActionList' is a list of MERGE actions
*/
ModifyTablePath *
create_modifytable_path(PlannerInfo *root, RelOptInfo *rel,
CmdType operation, bool canSetTag,
Index nominalRelation, List *partitioned_rels,
bool partColsUpdated,
- List *resultRelations, List *subpaths,
+ List *resultRelations,
+ List *mergeTargetRelations,
+ List *subpaths,
List *subroots,
List *withCheckOptionLists, List *returningLists,
List *rowMarks, OnConflictExpr *onconflict,
- int epqParam)
+ List *mergeSourceTargetLists,
+ List *mergeActionLists, int epqParam)
{
ModifyTablePath *pathnode = makeNode(ModifyTablePath);
double total_size;
@@ -3306,6 +3310,12 @@ create_modifytable_path(PlannerInfo *root, RelOptInfo *rel,
list_length(resultRelations) == list_length(withCheckOptionLists));
Assert(returningLists == NIL ||
list_length(resultRelations) == list_length(returningLists));
+ Assert(mergeSourceTargetLists == NIL ||
+ list_length(resultRelations) == list_length(mergeSourceTargetLists));
+ Assert(mergeActionLists == NIL ||
+ list_length(resultRelations) == list_length(mergeActionLists));
+ Assert(mergeTargetRelations == NIL ||
+ list_length(resultRelations) == list_length(mergeTargetRelations));
pathnode->path.pathtype = T_ModifyTable;
pathnode->path.parent = rel;
@@ -3359,6 +3369,7 @@ create_modifytable_path(PlannerInfo *root, RelOptInfo *rel,
pathnode->partitioned_rels = list_copy(partitioned_rels);
pathnode->partColsUpdated = partColsUpdated;
pathnode->resultRelations = resultRelations;
+ pathnode->mergeTargetRelations = mergeTargetRelations;
pathnode->subpaths = subpaths;
pathnode->subroots = subroots;
pathnode->withCheckOptionLists = withCheckOptionLists;
@@ -3366,6 +3377,8 @@ create_modifytable_path(PlannerInfo *root, RelOptInfo *rel,
pathnode->rowMarks = rowMarks;
pathnode->onconflict = onconflict;
pathnode->epqParam = epqParam;
+ pathnode->mergeSourceTargetLists = mergeSourceTargetLists;
+ pathnode->mergeActionLists = mergeActionLists;
return pathnode;
}
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index 60f2171..4457d483 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -1826,6 +1826,10 @@ has_row_triggers(PlannerInfo *root, Index rti, CmdType event)
trigDesc->trig_delete_before_row))
result = true;
break;
+ /* There is no separate event for MERGE, only INSERT/UPDATE/DELETE */
+ case CMD_MERGE:
+ result = false;
+ break;
default:
elog(ERROR, "unrecognized CmdType: %d", (int) event);
break;
diff --git a/src/backend/optimizer/util/relnode.c b/src/backend/optimizer/util/relnode.c
index 5c36832..e51c8a6 100644
--- a/src/backend/optimizer/util/relnode.c
+++ b/src/backend/optimizer/util/relnode.c
@@ -1237,7 +1237,6 @@ find_childrel_parents(PlannerInfo *root, RelOptInfo *rel)
return result;
}
-
/*
* get_baserel_parampathinfo
* Get the ParamPathInfo for a parameterized path for a base relation,
diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c
index e7b2bc7..2edd3d7 100644
--- a/src/backend/parser/analyze.c
+++ b/src/backend/parser/analyze.c
@@ -65,6 +65,7 @@ static Node *transformSetOperationTree(ParseState *pstate, SelectStmt *stmt,
static void determineRecursiveColTypes(ParseState *pstate,
Node *larg, List *nrtargetlist);
static Query *transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt);
+static Query *transformMergeStmt(ParseState *pstate, MergeStmt *stmt);
static List *transformReturningList(ParseState *pstate, List *returningList);
static List *transformUpdateTargetList(ParseState *pstate,
List *targetList);
@@ -263,6 +264,7 @@ transformStmt(ParseState *pstate, Node *parseTree)
case T_InsertStmt:
case T_UpdateStmt:
case T_DeleteStmt:
+ case T_MergeStmt:
(void) test_raw_expression_coverage(parseTree, NULL);
break;
default:
@@ -287,6 +289,10 @@ transformStmt(ParseState *pstate, Node *parseTree)
result = transformUpdateStmt(pstate, (UpdateStmt *) parseTree);
break;
+ case T_MergeStmt:
+ result = transformMergeStmt(pstate, (MergeStmt *) parseTree);
+ break;
+
case T_SelectStmt:
{
SelectStmt *n = (SelectStmt *) parseTree;
@@ -357,6 +363,7 @@ analyze_requires_snapshot(RawStmt *parseTree)
case T_InsertStmt:
case T_DeleteStmt:
case T_UpdateStmt:
+ case T_MergeStmt:
case T_SelectStmt:
result = true;
break;
@@ -2250,8 +2257,463 @@ transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt)
}
/*
+ * Make appropriate changes to the namespace visibility while transforming
+ * individual action's quals and targetlist expressions. In particular, for
+ * INSERT actions we must only see the source relation (since INSERT action is
+ * invoked for NOT MATCHED tuples and hence there is no target tuple to deal
+ * with). On the other hand, UPDATE and DELETE actions can see both source and
+ * target relations.
+ *
+ * Also, since the internal MergeJoin node can hide the source and target
+ * relations, we must explicitly make the respective relation as visible so
+ * that columns can be referenced unqualified from these relations.
+ */
+static void
+setNamespaceForMergeAction(ParseState *pstate, MergeAction *action)
+{
+ RangeTblEntry *targetRelRTE, *sourceRelRTE;
+
+ /* Assume target relation is at index 1 */
+ targetRelRTE = rt_fetch(1, pstate->p_rtable);
+
+ /*
+ * Assume that the top-level join RTE is at the end. The source relation is
+ * just before that.
+ */
+ sourceRelRTE = rt_fetch(list_length(pstate->p_rtable) - 1, pstate->p_rtable);
+
+ switch (action->commandType)
+ {
+ case CMD_INSERT:
+ /*
+ * Inserts can't see target relation, but they can see source
+ * relation.
+ */
+ setNamespaceVisibilityForRTE(pstate->p_namespace,
+ targetRelRTE, false, false);
+ setNamespaceVisibilityForRTE(pstate->p_namespace,
+ sourceRelRTE, true, true);
+ break;
+
+ case CMD_UPDATE:
+ case CMD_DELETE:
+ /*
+ * Updates and deletes can see both target and source relations.
+ */
+ setNamespaceVisibilityForRTE(pstate->p_namespace,
+ targetRelRTE, true, true);
+ setNamespaceVisibilityForRTE(pstate->p_namespace,
+ sourceRelRTE, true, true);
+ break;
+
+ case CMD_NOTHING:
+ break;
+ default:
+ elog(ERROR, "unknown action in MERGE WHEN clause");
+ }
+}
+
+/*
+ * transformMergeStmt -
+ * transforms a MERGE statement
+ */
+static Query *
+transformMergeStmt(ParseState *pstate, MergeStmt *stmt)
+{
+ Query *qry = makeNode(Query);
+ ListCell *l;
+ AclMode targetPerms = ACL_NO_RIGHTS;
+ bool is_terminal[2];
+ JoinExpr *joinexpr;
+
+ /* There can't be any outer WITH to worry about */
+ Assert(pstate->p_ctenamespace == NIL);
+
+ qry->commandType = CMD_MERGE;
+
+ /*
+ * Check WHEN clauses for permissions and sanity
+ */
+ is_terminal[0] = false;
+ is_terminal[1] = false;
+ foreach(l, stmt->mergeActionList)
+ {
+ MergeAction *action = (MergeAction *) lfirst(l);
+ uint when_type = (action->matched ? 0 : 1);
+
+ /*
+ * Collect action types so we can check Target permissions
+ */
+ switch (action->commandType)
+ {
+ case CMD_INSERT:
+ {
+ InsertStmt *istmt = (InsertStmt *) action->stmt;
+ SelectStmt *selectStmt = (SelectStmt *) istmt->selectStmt;
+
+ /*
+ * The grammar allows attaching ORDER BY, LIMIT, FOR UPDATE,
+ * or WITH to a VALUES clause and also multiple VALUES clauses.
+ * If we have any of those, ERROR.
+ */
+ if (selectStmt && (selectStmt->valuesLists == NIL ||
+ selectStmt->sortClause != NIL ||
+ selectStmt->limitOffset != NULL ||
+ selectStmt->limitCount != NULL ||
+ selectStmt->lockingClause != NIL ||
+ selectStmt->withClause != NULL))
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("SELECT not allowed in MERGE INSERT statement")));
+
+ if (selectStmt && list_length(selectStmt->valuesLists) > 1)
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("Multiple VALUES clauses not allowed in MERGE INSERT statement")));
+
+ targetPerms |= ACL_INSERT;
+ }
+ break;
+ case CMD_UPDATE:
+ targetPerms |= ACL_UPDATE;
+ break;
+ case CMD_DELETE:
+ targetPerms |= ACL_DELETE;
+ break;
+ case CMD_NOTHING:
+ break;
+ default:
+ elog(ERROR, "unknown action in MERGE WHEN clause");
+ }
+
+ /*
+ * Check for unreachable WHEN clauses
+ */
+ if (action->condition == NULL)
+ is_terminal[when_type] = true;
+ else if (is_terminal[when_type])
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("unreachable WHEN clause specified after unconditional WHEN clause")));
+ }
+
+ /*
+ * Construct a query of the form
+ * SELECT relation.ctid --junk attribute
+ * ,relation.tableoid --junk attribute
+ * ,source_relation.
+ * ,relation.
+ * FROM relation RIGHT JOIN source_relation
+ * ON join_condition
+ * -- no WHERE clause - all conditions are applied in executor
+ *
+ * stmt->relation is the target relation, given as a RangeVar
+ * stmt->source_relation is a RangeVar or subquery
+ *
+ * We specify the join as a RIGHT JOIN as a simple way of forcing
+ * the first (larg) RTE to refer to the target table.
+ *
+ * The MERGE query's join can be tuned in some cases, see below
+ * for these special case tweaks.
+ *
+ * We set QSRC_PARSER to show query constructed in parse analysis
+ *
+ * Note that we have only one Query for a MERGE statement and
+ * the planner is called only once. That query is executed once
+ * to produce our stream of candidate change rows, so the query
+ * must contain all of the columns required by each of the
+ * targetlist or conditions for each action.
+ *
+ * As top-level statements INSERT, UPDATE and DELETE have a Query,
+ * whereas with MERGE the individual actions do not require
+ * separate planning, only different handling in the executor.
+ * See nodeModifyTable handling of commandType CMD_MERGE.
+ *
+ * A sub-query can include the Target, but otherwise the sub-query
+ * cannot reference the outermost Target table at all.
+ */
+ qry->querySource = QSRC_PARSER;
+
+ /*
+ * Setup the target table. We expand inheritance like in the case of
+ * UPDATE/DELETE and unlike INSERT. This ensures that all the machinery
+ * required for handling inheritance/partitioning is setup correctly. This
+ * is useful in order to handle various MERGE actions as we need to
+ * evaluate WHEN conditions and project tuples suitable for the target
+ * relation.
+ *
+ * As a result, the final ModifyTable node which gets added at the top,
+ * will have the result relations set up correctly, with the corresponding
+ * subplans. But we don't follow the usual approach of executing these
+ * subplans one by one. Instead we include the target table in the
+ * underlying JOIN query as a separate RTE. The target table gets expanded
+ * into an Append rel in case of partitioned table and thus the join
+ * ensures that all required tuples are returned correctly. Hence executing
+ * just one subplan gives us all the desired matching and non-matching
+ * tuples.
+ */
+ qry->resultRelation = setTargetTable(pstate, stmt->relation,
+ stmt->relation->inh,
+ true, targetPerms);
+
+ joinexpr = makeNode(JoinExpr);
+ joinexpr->isNatural = false;
+ joinexpr->alias = NULL;
+ joinexpr->usingClause = NIL;
+ joinexpr->quals = stmt->join_condition;
+
+ /*
+ * Simplify the MERGE query as much as possible
+ *
+ * These seem like things that could go into Optimizer, but
+ * they are semantic simplications rather than optimizations, per se.
+ *
+ * If there are no INSERT actions we won't be using the non-matching
+ * candidate rows for anything, so no need for an outer join. We
+ * do still need an inner join for UPDATE and DELETE actions.
+ *
+ * Possible additional simplifications...
+ *
+ * XXX if we have a constant ON clause, we can skip join altogether
+ *
+ * XXX if we have a constant subquery, we can also skip join
+ *
+ * XXX if we were really keen we could look through the actionList
+ * and pull out common conditions, if there were no terminal clauses
+ * and put them into the main query as an early row filter
+ * but that seems like an atypical case and so checking for it
+ * would be likely to just be wasted effort.
+ */
+ joinexpr->larg = (Node *) stmt->relation;
+ joinexpr->rarg = (Node *) stmt->source_relation;
+ if (targetPerms & ACL_INSERT)
+ joinexpr->jointype = JOIN_RIGHT;
+ else
+ joinexpr->jointype = JOIN_INNER;
+
+ /*
+ * We use a special purpose transformation here because the normal
+ * routines don't quite work right for the MERGE case.
+ *
+ * A special mergeSourceTargetList is setup by transformMergeJoinClause().
+ * It refers to all the attributes provided by the source relation. This is
+ * later used by set_plan_refs() to fix the UPDATE/INSERT target lists to
+ * so that they can correctly fetch the attributes from the source
+ * relation.
+ *
+ * Track the RTE index of the target table used in the join query. This is
+ * later used to add required junk attributes to the targetlist.
+ */
+ qry->mergeTarget_relation = transformMergeJoinClause(pstate, (Node *) joinexpr,
+ &qry->mergeSourceTargetList);
+
+ /*
+ * This query should just provide the source relation columns. Later, in
+ * preprocess_targetlist(), we shall also add "ctid" attribute of the
+ * target relation to ensure that the target tuple can be fetched
+ * correctly.
+ */
+ qry->targetList = qry->mergeSourceTargetList;
+
+ /* qry has no WHERE clause so absent quals are shown as NULL */
+ qry->jointree = makeFromExpr(pstate->p_joinlist, NULL);
+ qry->rtable = pstate->p_rtable;
+
+ /*
+ * XXX MERGE is unsupported in various cases
+ */
+ if (!(pstate->p_target_relation->rd_rel->relkind == RELKIND_RELATION ||
+ pstate->p_target_relation->rd_rel->relkind == RELKIND_MATVIEW ||
+ pstate->p_target_relation->rd_rel->relkind == RELKIND_PARTITIONED_TABLE))
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("MERGE is not supported for this relation type")));
+
+ if (pstate->p_target_relation->rd_rel->relkind != RELKIND_PARTITIONED_TABLE &&
+ pstate->p_target_relation->rd_rel->relhassubclass)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("MERGE is not supported for relations with inheritance")));
+
+ /*
+ * We now have a good query shape, so now look at the when conditions
+ * and action targetlists.
+ *
+ * Overall, the MERGE Query's targetlist is NIL.
+ *
+ * Each individual action has its own targetlist that needs separate
+ * transformation. These transforms don't do anything to the overall
+ * targetlist, since that is only used for resjunk columns.
+ *
+ * We can reference any column in Target or Source, which is OK
+ * because both of those already have RTEs. There is nothing like
+ * the EXCLUDED pseudo-relation for INSERT ON CONFLICT.
+ */
+ foreach(l, stmt->mergeActionList)
+ {
+ MergeAction *action = (MergeAction *) lfirst(l);
+
+ /*
+ * Set namespace for the specific action. This must be done before
+ * analysing the WHEN quals and the action targetlisst.
+ *
+ * XXX Do we need to restore the old values back?
+ */
+ setNamespaceForMergeAction(pstate, action);
+
+ /*
+ * Transform the when condition.
+ *
+ * We don't have a separate plan for each action, so the
+ * when condition must be executed as a per-row check,
+ * making it very similar to a CHECK constraint and so we
+ * adopt the same semantics for that.
+ *
+ * SQL Standard says we should not allow anything that possibly
+ * modifies SQL-data. We enforce that with an executor check
+ * that we have not written any WAL.
+ *
+ * XXX Perhaps we require Parallel Safety since that is a superset
+ * of the restriction and enforcing that makes it easier to
+ * consider running MERGE plans in parallel in future.
+ *
+ * Note that we don't add this to the MERGE Query's quals
+ * because that's not the logic MERGE uses.
+ */
+ action->qual = transformWhereClause(pstate, action->condition,
+ EXPR_KIND_MERGE_WHEN_AND, "WHEN");
+
+ /*
+ * Transform target lists for each INSERT and UPDATE action stmt
+ */
+ switch (action->commandType)
+ {
+ case CMD_INSERT:
+ {
+ InsertStmt *istmt = (InsertStmt *) action->stmt;
+ SelectStmt *selectStmt = (SelectStmt *) istmt->selectStmt;
+ List *exprList = NIL;
+ ListCell *lc;
+ RangeTblEntry *rte;
+ ListCell *icols;
+ ListCell *attnos;
+ List *icolumns;
+ List *attrnos;
+
+ pstate->p_is_insert = true;
+
+ icolumns = checkInsertTargets(pstate, istmt->cols, &attrnos);
+ Assert(list_length(icolumns) == list_length(attrnos));
+
+ /*
+ * Handle INSERT much like in transformInsertStmt
+ *
+ * XXX currently ignore stmt->override, if present
+ */
+ if (selectStmt == NULL)
+ {
+ /*
+ * We have INSERT ... DEFAULT VALUES. We can handle this case by
+ * emitting an empty targetlist --- all columns will be defaulted when
+ * the planner expands the targetlist.
+ */
+ exprList = NIL;
+ }
+ else
+ {
+ /*
+ * Process INSERT ... VALUES with a single VALUES sublist. We treat
+ * this case separately for efficiency. The sublist is just computed
+ * directly as the Query's targetlist, with no VALUES RTE. So it
+ * works just like a SELECT without any FROM.
+ */
+ List *valuesLists = selectStmt->valuesLists;
+
+ Assert(list_length(valuesLists) == 1);
+ Assert(selectStmt->intoClause == NULL);
+
+ /*
+ * Do basic expression transformation (same as a ROW() expr, but allow
+ * SetToDefault at top level)
+ */
+ exprList = transformExpressionList(pstate,
+ (List *) linitial(valuesLists),
+ EXPR_KIND_VALUES_SINGLE,
+ true);
+
+ /* Prepare row for assignment to target table */
+ exprList = transformInsertRow(pstate, exprList,
+ istmt->cols,
+ icolumns, attrnos,
+ false);
+ }
+
+ /*
+ * Generate action's target list using the computed list of expressions.
+ * Also, mark all the target columns as needing insert permissions.
+ */
+ rte = pstate->p_target_rangetblentry;
+ icols = list_head(icolumns);
+ attnos = list_head(attrnos);
+ foreach(lc, exprList)
+ {
+ Expr *expr = (Expr *) lfirst(lc);
+ ResTarget *col;
+ AttrNumber attr_num;
+ TargetEntry *tle;
+
+ col = lfirst_node(ResTarget, icols);
+ attr_num = (AttrNumber) lfirst_int(attnos);
+
+ tle = makeTargetEntry(expr,
+ attr_num,
+ col->name,
+ false);
+ action->targetList = lappend(action->targetList, tle);
+
+ rte->insertedCols = bms_add_member(rte->insertedCols,
+ attr_num - FirstLowInvalidHeapAttributeNumber);
+
+ icols = lnext(icols);
+ attnos = lnext(attnos);
+ }
+ }
+ break;
+ case CMD_UPDATE:
+ {
+ UpdateStmt *ustmt = (UpdateStmt *) action->stmt;
+
+ pstate->p_is_insert = false;
+ action->targetList = transformUpdateTargetList(pstate, ustmt->targetList);
+ }
+ break;
+ case CMD_DELETE:
+ break;
+
+ case CMD_NOTHING:
+ action->targetList = NIL;
+ break;
+ default:
+ elog(ERROR, "unknown action in MERGE WHEN clause");
+ }
+ }
+
+ qry->mergeActionList = stmt->mergeActionList;
+
+ /* XXX maybe later */
+ qry->returningList = NULL;
+
+ qry->hasTargetSRFs = false;
+ qry->hasSubLinks = pstate->p_hasSubLinks;
+
+ assign_query_collations(pstate, qry);
+
+ return qry;
+}
+
+/*
* transformUpdateTargetList -
- * handle SET clause in UPDATE/INSERT ... ON CONFLICT UPDATE
+ * handle SET clause in UPDATE/MERGE/INSERT ... ON CONFLICT UPDATE
*/
static List *
transformUpdateTargetList(ParseState *pstate, List *origTlist)
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index d99f2be..3dc249c 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -282,6 +282,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
CreateMatViewStmt RefreshMatViewStmt CreateAmStmt
CreatePublicationStmt AlterPublicationStmt
CreateSubscriptionStmt AlterSubscriptionStmt DropSubscriptionStmt
+ MergeStmt
%type select_no_parens select_with_parens select_clause
simple_select values_clause
@@ -583,6 +584,10 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
%type hash_partbound partbound_datum_list range_datum_list
%type hash_partbound_elem
+%type merge_when_clause opt_and_condition
+%type merge_when_list
+%type merge_update merge_delete merge_insert
+
/*
* Non-keyword token types. These are hard-wired into the "flex" lexer.
* They must be listed first so that their numeric codes do not depend on
@@ -650,7 +655,8 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
LEADING LEAKPROOF LEAST LEFT LEVEL LIKE LIMIT LISTEN LOAD LOCAL
LOCALTIME LOCALTIMESTAMP LOCATION LOCK_P LOCKED LOGGED
- MAPPING MATCH MATERIALIZED MAXVALUE METHOD MINUTE_P MINVALUE MODE MONTH_P MOVE
+ MAPPING MATCH MATCHED MATERIALIZED MAXVALUE MERGE METHOD
+ MINUTE_P MINVALUE MODE MONTH_P MOVE
NAME_P NAMES NATIONAL NATURAL NCHAR NEW NEXT NO NONE
NOT NOTHING NOTIFY NOTNULL NOWAIT NULL_P NULLIF
@@ -919,6 +925,7 @@ stmt :
| RefreshMatViewStmt
| LoadStmt
| LockStmt
+ | MergeStmt
| NotifyStmt
| PrepareStmt
| ReassignOwnedStmt
@@ -10645,6 +10652,7 @@ ExplainableStmt:
| InsertStmt
| UpdateStmt
| DeleteStmt
+ | MergeStmt
| DeclareCursorStmt
| CreateAsStmt
| CreateMatViewStmt
@@ -10707,6 +10715,7 @@ PreparableStmt:
| InsertStmt
| UpdateStmt
| DeleteStmt /* by default all are $$=$1 */
+ | MergeStmt
;
/*****************************************************************************
@@ -11076,6 +11085,151 @@ set_target_list:
/*****************************************************************************
*
* QUERY:
+ * MERGE STATEMENT
+ *
+ *****************************************************************************/
+
+MergeStmt:
+ MERGE INTO relation_expr_opt_alias
+ USING table_ref
+ ON a_expr
+ merge_when_list
+ {
+ MergeStmt *m = makeNode(MergeStmt);
+
+ m->relation = $3;
+ m->source_relation = $5;
+ m->join_condition = $7;
+ m->mergeActionList = $8;
+
+ $$ = (Node *)m;
+ }
+ ;
+
+
+merge_when_list:
+ merge_when_clause { $$ = list_make1($1); }
+ | merge_when_list merge_when_clause { $$ = lappend($1,$2); }
+ ;
+
+merge_when_clause:
+ WHEN MATCHED opt_and_condition THEN merge_update
+ {
+ MergeAction *m = makeNode(MergeAction);
+
+ m->matched = true;
+ m->commandType = CMD_UPDATE;
+ m->condition = $3;
+ m->stmt = $5;
+
+ $$ = (Node *)m;
+ }
+ | WHEN MATCHED opt_and_condition THEN merge_delete
+ {
+ MergeAction *m = makeNode(MergeAction);
+
+ m->matched = true;
+ m->commandType = CMD_DELETE;
+ m->condition = $3;
+ m->stmt = $5;
+
+ $$ = (Node *)m;
+ }
+ | WHEN NOT MATCHED opt_and_condition THEN merge_insert
+ {
+ MergeAction *m = makeNode(MergeAction);
+
+ m->matched = false;
+ m->commandType = CMD_INSERT;
+ m->condition = $4;
+ m->stmt = $6;
+
+ $$ = (Node *)m;
+ }
+ | WHEN NOT MATCHED opt_and_condition THEN DO NOTHING
+ {
+ MergeAction *m = makeNode(MergeAction);
+
+ m->matched = false;
+ m->commandType = CMD_NOTHING;
+ m->condition = $4;
+ m->stmt = NULL;
+
+ $$ = (Node *)m;
+ }
+ ;
+
+opt_and_condition:
+ AND a_expr { $$ = $2; }
+ | { $$ = NULL; }
+ ;
+
+merge_delete:
+ DELETE_P
+ {
+ DeleteStmt *n = makeNode(DeleteStmt);
+ $$ = (Node *)n;
+ }
+ ;
+
+merge_update:
+ UPDATE SET set_clause_list
+ {
+ UpdateStmt *n = makeNode(UpdateStmt);
+ n->targetList = $3;
+
+ $$ = (Node *)n;
+ }
+ ;
+
+merge_insert:
+ INSERT values_clause
+ {
+ InsertStmt *n = makeNode(InsertStmt);
+ n->cols = NIL;
+ n->selectStmt = $2;
+
+ $$ = (Node *)n;
+ }
+ | INSERT OVERRIDING override_kind VALUE_P values_clause
+ {
+ InsertStmt *n = makeNode(InsertStmt);
+ n->cols = NIL;
+ n->override = $3;
+ n->selectStmt = $5;
+
+ $$ = (Node *)n;
+ }
+ | INSERT '(' insert_column_list ')' values_clause
+ {
+ InsertStmt *n = makeNode(InsertStmt);
+ n->cols = $3;
+ n->selectStmt = $5;
+
+ $$ = (Node *)n;
+ }
+ | INSERT '(' insert_column_list ')' OVERRIDING override_kind VALUE_P values_clause
+ {
+ InsertStmt *n = makeNode(InsertStmt);
+ n->cols = $3;
+ n->override = $6;
+ n->selectStmt = $8;
+
+ $$ = (Node *)n;
+ }
+ | INSERT DEFAULT VALUES
+ {
+ InsertStmt *n = makeNode(InsertStmt);
+ n->cols = NIL;
+ n->selectStmt = NULL;
+
+ $$ = (Node *)n;
+ }
+ ;
+
+/*****************************************************************************
+ *
+ * QUERY:
* CURSOR STATEMENTS
*
*****************************************************************************/
@@ -15073,8 +15227,10 @@ unreserved_keyword:
| LOGGED
| MAPPING
| MATCH
+ | MATCHED
| MATERIALIZED
| MAXVALUE
+ | MERGE
| METHOD
| MINUTE_P
| MINVALUE
diff --git a/src/backend/parser/parse_agg.c b/src/backend/parser/parse_agg.c
index 377a7ed..544e730 100644
--- a/src/backend/parser/parse_agg.c
+++ b/src/backend/parser/parse_agg.c
@@ -455,6 +455,13 @@ check_agglevels_and_constraints(ParseState *pstate, Node *expr)
case EXPR_KIND_VALUES_SINGLE:
errkind = true;
break;
+ case EXPR_KIND_MERGE_WHEN_AND:
+ if (isAgg)
+ err = _("aggregate functions are not allowed in WHEN AND conditions");
+ else
+ err = _("grouping operations are not allowed in WHEN AND conditions");
+
+ break;
case EXPR_KIND_CHECK_CONSTRAINT:
case EXPR_KIND_DOMAIN_CHECK:
if (isAgg)
@@ -873,6 +880,9 @@ transformWindowFuncCall(ParseState *pstate, WindowFunc *wfunc,
case EXPR_KIND_VALUES_SINGLE:
errkind = true;
break;
+ case EXPR_KIND_MERGE_WHEN_AND:
+ err = _("window functions are not allowed in WHEN AND conditions");
+ break;
case EXPR_KIND_CHECK_CONSTRAINT:
case EXPR_KIND_DOMAIN_CHECK:
err = _("window functions are not allowed in check constraints");
diff --git a/src/backend/parser/parse_clause.c b/src/backend/parser/parse_clause.c
index 3a02307..34302b9 100644
--- a/src/backend/parser/parse_clause.c
+++ b/src/backend/parser/parse_clause.c
@@ -31,6 +31,7 @@
#include "commands/defrem.h"
#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
+#include "nodes/print.h"
#include "optimizer/tlist.h"
#include "optimizer/var.h"
#include "parser/analyze.h"
@@ -78,6 +79,7 @@ static TableSampleClause *transformRangeTableSample(ParseState *pstate,
RangeTableSample *rts);
static Node *transformFromClauseItem(ParseState *pstate, Node *n,
RangeTblEntry **top_rte, int *top_rti,
+ RangeTblEntry **right_rte, int *right_rti,
List **namespace);
static Node *buildMergedJoinVar(ParseState *pstate, JoinType jointype,
Var *l_colvar, Var *r_colvar);
@@ -139,6 +141,7 @@ transformFromClause(ParseState *pstate, List *frmList)
n = transformFromClauseItem(pstate, n,
&rte,
&rtindex,
+ NULL, NULL,
&namespace);
checkNameSpaceConflicts(pstate, pstate->p_namespace, namespace);
@@ -160,6 +163,89 @@ transformFromClause(ParseState *pstate, List *frmList)
}
/*
+ * Special handling for MERGE statement is required because we assemble
+ * the query manually. This is similar to setTargetTable() followed
+ * by transformFromClause() but with a few less steps.
+ *
+ * Process the FROM clause and add items to the query's range table,
+ * joinlist, and namespace.
+ *
+ * Note: we assume that the pstate's p_rtable, p_joinlist, and p_namespace
+ * lists were initialized to NIL when the pstate was created.
+ *
+ * A special targetlist comprising of the columns from the right-subtree of
+ * the join is populated and returned. Note that when the JoinExpr is
+ * setup by transformMergeStmt, the left subtree has the target result
+ * relation and the right subtree has the source relation.
+ *
+ * Returns the rangetable index of the target relation.
+ */
+int
+transformMergeJoinClause(ParseState *pstate, Node *merge,
+ List **mergeSourceTargetList)
+{
+ RangeTblEntry *rte, *rt_rte;
+ List *namespace;
+ int rtindex, rt_rtindex;
+ Node *n;
+ int mergeTarget_relation = list_length(pstate->p_rtable) + 1;
+ Var *var;
+ TargetEntry *te;
+
+ n = transformFromClauseItem(pstate, merge,
+ &rte,
+ &rtindex,
+ &rt_rte,
+ &rt_rtindex,
+ &namespace);
+
+ pstate->p_joinlist = list_make1(n);
+
+ /*
+ * We created an internal join between the target and the source relation
+ * to carry out the MERGE actions. Normally such an unaliased join hides
+ * the joining relations, unless the column references are qualified. Also,
+ * any unqualified column refernces are resolved to the Join RTE, if there
+ * is a matching entry in the targetlist. But the way MERGE execution is
+ * later setup, we expect all column references to resolve to either the
+ * source or the target relation. Hence we must not add the Join RTE to the
+ * namespace.
+ *
+ * The last entry must be for the top-level Join RTE. The source (right
+ * side of the join) RTE must have been placed just before that. Keep that
+ * and discard everything else. More importantly, we want to discard the
+ * RTE of the left side of the join since that contains the target
+ * relation. References to the columns of the target relation must be
+ * resolved from the result relation and not the one that is used in the
+ * join.
+ */
+ Assert(list_length(namespace) > 1);
+ namespace = list_truncate(namespace, list_length(namespace) - 1);
+ pstate->p_namespace = lappend(pstate->p_namespace, llast(namespace));
+
+ /* XXX Do we need this? */
+ setNamespaceLateralState(pstate->p_namespace, false, true);
+
+ /*
+ * Expand the right relation and add its columns to the
+ * mergeSourceTargetList. Note that the right relation can either be a
+ * plain relation or a subquery or anything that can have a
+ * RangeTableEntry.
+ */
+ *mergeSourceTargetList = expandRelAttrs(pstate, rt_rte, rt_rtindex, 0, -1);
+
+ /*
+ * Add a whole-row-Var entry to support references to "source.*".
+ */
+ var = makeWholeRowVar(rt_rte, rt_rtindex, 0, false);
+ te = makeTargetEntry((Expr *) var, list_length(*mergeSourceTargetList) + 1,
+ NULL, true);
+ *mergeSourceTargetList = lappend(*mergeSourceTargetList, te);
+
+ return mergeTarget_relation;
+}
+
+/*
* setTargetTable
* Add the target relation of INSERT/UPDATE/DELETE to the range table,
* and make the special links to it in the ParseState.
@@ -1103,6 +1189,7 @@ getRTEForSpecialRelationTypes(ParseState *pstate, RangeVar *rv)
static Node *
transformFromClauseItem(ParseState *pstate, Node *n,
RangeTblEntry **top_rte, int *top_rti,
+ RangeTblEntry **right_rte, int *right_rti,
List **namespace)
{
if (IsA(n, RangeVar))
@@ -1194,7 +1281,7 @@ transformFromClauseItem(ParseState *pstate, Node *n,
/* Recursively transform the contained relation */
rel = transformFromClauseItem(pstate, rts->relation,
- top_rte, top_rti, namespace);
+ top_rte, top_rti, NULL, NULL, namespace);
/* Currently, grammar could only return a RangeVar as contained rel */
rtr = castNode(RangeTblRef, rel);
rte = rt_fetch(rtr->rtindex, pstate->p_rtable);
@@ -1240,6 +1327,7 @@ transformFromClauseItem(ParseState *pstate, Node *n,
j->larg = transformFromClauseItem(pstate, j->larg,
&l_rte,
&l_rtindex,
+ NULL, NULL,
&l_namespace);
/*
@@ -1267,6 +1355,7 @@ transformFromClauseItem(ParseState *pstate, Node *n,
j->rarg = transformFromClauseItem(pstate, j->rarg,
&r_rte,
&r_rtindex,
+ NULL, NULL,
&r_namespace);
/* Remove the left-side RTEs from the namespace list again */
@@ -1295,6 +1384,12 @@ transformFromClauseItem(ParseState *pstate, Node *n,
expandRTE(r_rte, r_rtindex, 0, -1, false,
&r_colnames, &r_colvars);
+ if (right_rte)
+ *right_rte = r_rte;
+
+ if (right_rti)
+ *right_rti = r_rtindex;
+
/*
* Natural join does not explicitly specify columns; must generate
* columns to join. Need to run through the list of columns from each
@@ -1692,6 +1787,27 @@ setNamespaceColumnVisibility(List *namespace, bool cols_visible)
}
}
+void
+setNamespaceVisibilityForRTE(List *namespace, RangeTblEntry *rte,
+ bool rel_visible,
+ bool cols_visible)
+{
+ ListCell *lc;
+
+ foreach(lc, namespace)
+ {
+ ParseNamespaceItem *nsitem = (ParseNamespaceItem *) lfirst(lc);
+
+ if (nsitem->p_rte == rte)
+ {
+ nsitem->p_rel_visible = rel_visible;
+ nsitem->p_cols_visible = cols_visible;
+ break;
+ }
+ }
+
+}
+
/*
* setNamespaceLateralState -
* Convenience subroutine to update LATERAL flags in a namespace list.
diff --git a/src/backend/parser/parse_collate.c b/src/backend/parser/parse_collate.c
index 6d34245..51c73c4 100644
--- a/src/backend/parser/parse_collate.c
+++ b/src/backend/parser/parse_collate.c
@@ -485,6 +485,7 @@ assign_collations_walker(Node *node, assign_collations_context *context)
case T_FromExpr:
case T_OnConflictExpr:
case T_SortGroupClause:
+ case T_MergeAction:
(void) expression_tree_walker(node,
assign_collations_walker,
(void *) &loccontext);
diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c
index 385e54a..ad89d7d 100644
--- a/src/backend/parser/parse_expr.c
+++ b/src/backend/parser/parse_expr.c
@@ -1818,6 +1818,7 @@ transformSubLink(ParseState *pstate, SubLink *sublink)
case EXPR_KIND_RETURNING:
case EXPR_KIND_VALUES:
case EXPR_KIND_VALUES_SINGLE:
+ case EXPR_KIND_MERGE_WHEN_AND:
/* okay */
break;
case EXPR_KIND_CHECK_CONSTRAINT:
@@ -3473,6 +3474,8 @@ ParseExprKindName(ParseExprKind exprKind)
return "WHEN";
case EXPR_KIND_PARTITION_EXPRESSION:
return "PARTITION BY";
+ case EXPR_KIND_MERGE_WHEN_AND:
+ return "MERGE WHEN AND";
case EXPR_KIND_CALL_ARGUMENT:
return "CALL";
diff --git a/src/backend/parser/parse_func.c b/src/backend/parser/parse_func.c
index 2a4ac09..d9d7770 100644
--- a/src/backend/parser/parse_func.c
+++ b/src/backend/parser/parse_func.c
@@ -2264,6 +2264,9 @@ check_srf_call_placement(ParseState *pstate, Node *last_srf, int location)
/* okay, since we process this like a SELECT tlist */
pstate->p_hasTargetSRFs = true;
break;
+ case EXPR_KIND_MERGE_WHEN_AND:
+ err = _("set-returning functions are not allowed in WHEN AND conditions");
+ break;
case EXPR_KIND_CHECK_CONSTRAINT:
case EXPR_KIND_DOMAIN_CHECK:
err = _("set-returning functions are not allowed in check constraints");
diff --git a/src/backend/parser/parse_relation.c b/src/backend/parser/parse_relation.c
index 053ae02..5583404 100644
--- a/src/backend/parser/parse_relation.c
+++ b/src/backend/parser/parse_relation.c
@@ -728,6 +728,16 @@ scanRTEForColumn(ParseState *pstate, RangeTblEntry *rte, const char *colname,
colname),
parser_errposition(pstate, location)));
+ /* In MERGE when and condition, no system column is allowed */
+ if (pstate->p_expr_kind == EXPR_KIND_MERGE_WHEN_AND &&
+ attnum < InvalidAttrNumber &&
+ !(attnum == TableOidAttributeNumber || attnum == ObjectIdAttributeNumber))
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
+ errmsg("system column \"%s\" reference in WHEN AND condition is invalid",
+ colname),
+ parser_errposition(pstate, location)));
+
if (attnum != InvalidAttrNumber)
{
/* now check to see if column actually is defined */
diff --git a/src/backend/rewrite/rewriteHandler.c b/src/backend/rewrite/rewriteHandler.c
index 66253fc..3d1622e 100644
--- a/src/backend/rewrite/rewriteHandler.c
+++ b/src/backend/rewrite/rewriteHandler.c
@@ -1376,6 +1376,54 @@ rewriteTargetListUD(Query *parsetree, RangeTblEntry *target_rte,
}
}
+void
+rewriteTargetListMerge(Query *parsetree, Relation target_relation)
+{
+ Var *var = NULL;
+ const char *attrname;
+ TargetEntry *tle;
+
+ if (target_relation->rd_rel->relkind == RELKIND_RELATION ||
+ target_relation->rd_rel->relkind == RELKIND_MATVIEW ||
+ target_relation->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
+ {
+ /*
+ * Emit CTID so that executor can find the row to update or delete.
+ */
+ var = makeVar(parsetree->mergeTarget_relation,
+ SelfItemPointerAttributeNumber,
+ TIDOID,
+ -1,
+ InvalidOid,
+ 0);
+
+ attrname = "ctid";
+ tle = makeTargetEntry((Expr *) var,
+ list_length(parsetree->targetList) + 1,
+ pstrdup(attrname),
+ true);
+
+ parsetree->targetList = lappend(parsetree->targetList, tle);
+
+ /*
+ * Emit TABLEOID so that executor can find the row to update or delete.
+ */
+ var = makeVar(parsetree->mergeTarget_relation,
+ TableOidAttributeNumber,
+ OIDOID,
+ -1,
+ InvalidOid,
+ 0);
+
+ attrname = "tableoid";
+ tle = makeTargetEntry((Expr *) var,
+ list_length(parsetree->targetList) + 1,
+ pstrdup(attrname),
+ true);
+
+ parsetree->targetList = lappend(parsetree->targetList, tle);
+ }
+}
/*
* matchLocks -
@@ -3330,13 +3378,57 @@ RewriteQuery(Query *parsetree, List *rewrite_events)
}
else if (event == CMD_UPDATE)
{
+ Assert(parsetree->override == OVERRIDING_NOT_SET);
parsetree->targetList =
- rewriteTargetListIU(parsetree->targetList,
+ rewriteTargetListIU(parsetree->targetList,
parsetree->commandType,
parsetree->override,
rt_entry_relation,
parsetree->resultRelation, NULL);
}
+ else if (event == CMD_MERGE)
+ {
+ Assert(parsetree->override == OVERRIDING_NOT_SET);
+
+ /*
+ * Rewrite each action targetlist separately
+ */
+ foreach(lc1, parsetree->mergeActionList)
+ {
+ MergeAction *action = (MergeAction *) lfirst(lc1);
+
+ switch (action->commandType)
+ {
+ case CMD_NOTHING:
+ case CMD_DELETE: /* Nothing to do here */
+ break;
+ case CMD_UPDATE:
+ action->targetList =
+ rewriteTargetListIU(action->targetList,
+ action->commandType,
+ parsetree->override,
+ rt_entry_relation,
+ parsetree->resultRelation,
+ NULL);
+ break;
+ case CMD_INSERT:
+ {
+ InsertStmt *istmt = (InsertStmt *) action->stmt;
+ action->targetList =
+ rewriteTargetListIU(action->targetList,
+ action->commandType,
+ istmt->override,
+ rt_entry_relation,
+ parsetree->resultRelation,
+ NULL);
+ }
+ break;
+ default:
+ elog(ERROR, "unrecognized commandType: %d", action->commandType);
+ break;
+ }
+ }
+ }
else if (event == CMD_DELETE)
{
/* Nothing to do here */
@@ -3350,7 +3442,13 @@ RewriteQuery(Query *parsetree, List *rewrite_events)
locks = matchLocks(event, rt_entry_relation->rd_rules,
result_relation, parsetree, &hasUpdate);
- product_queries = fireRules(parsetree,
+ /*
+ * First rule of MERGE club is we don't talk about rules
+ */
+ if (event == CMD_MERGE)
+ product_queries = NIL;
+ else
+ product_queries = fireRules(parsetree,
result_relation,
event,
locks,
diff --git a/src/backend/rewrite/rowsecurity.c b/src/backend/rewrite/rowsecurity.c
index ce77a18..98be4b9 100644
--- a/src/backend/rewrite/rowsecurity.c
+++ b/src/backend/rewrite/rowsecurity.c
@@ -379,6 +379,95 @@ get_row_security_policies(Query *root, RangeTblEntry *rte, int rt_index,
}
}
+ /*
+ * FOR MERGE, we fetch policies for UPDATE, DELETE and INSERT (and ALL) and
+ * set them up so that we can enforce the appropriate policy depending on
+ * the final action we take.
+ *
+ * We don't fetch the SELECT policies since they are correctly applied to
+ * the root->mergeTarget_relation. The target rows are selected after
+ * joining the mergeTarget_relation and the source relation and hence it's
+ * enough to apply SELECT policies to the mergeTarget_relation.
+ *
+ * We don't push the UPDATE/DELETE USING quals to the RTE because we don't
+ * really want to apply them while scanning the relation since we don't
+ * know whether we will be doing a UPDATE or a DELETE at the end. We apply
+ * the respective policy once we decide the final action on the target
+ * tuple.
+ *
+ * XXX We are setting up USING quals as WITH CHECK. If RLS prohibits
+ * UPDATE/DELETE on the target row, we shall throw an error instead of
+ * silently ignoring the row. This is different than how normal
+ * UPDATE/DELETE works and more in line with INSERT ON CONFLICT DO UPDATE
+ * handling.
+ */
+ if (commandType == CMD_MERGE)
+ {
+ List *merge_permissive_policies;
+ List *merge_restrictive_policies;
+
+ /*
+ * Fetch the UPDATE policies and set them up to execute on the existing
+ * target row before doing UPDATE.
+ */
+ get_policies_for_relation(rel, CMD_UPDATE, user_id,
+ &merge_permissive_policies,
+ &merge_restrictive_policies);
+
+ /*
+ * WCO_RLS_MERGE_UPDATE_CHECK is used to check UPDATE USING quals on
+ * the existing target row.
+ */
+ add_with_check_options(rel, rt_index,
+ WCO_RLS_MERGE_UPDATE_CHECK,
+ merge_permissive_policies,
+ merge_restrictive_policies,
+ withCheckOptions,
+ hasSubLinks,
+ true);
+
+ /*
+ * Same with DELETE policies.
+ */
+ get_policies_for_relation(rel, CMD_DELETE, user_id,
+ &merge_permissive_policies,
+ &merge_restrictive_policies);
+
+ add_with_check_options(rel, rt_index,
+ WCO_RLS_MERGE_DELETE_CHECK,
+ merge_permissive_policies,
+ merge_restrictive_policies,
+ withCheckOptions,
+ hasSubLinks,
+ true);
+
+ /*
+ * No special handling is required for INSERT policies. They will be
+ * checked and enforced during ExecInsert(). But we must add them to
+ * withCheckOptions.
+ */
+ get_policies_for_relation(rel, CMD_INSERT, user_id,
+ &merge_permissive_policies,
+ &merge_restrictive_policies);
+
+ add_with_check_options(rel, rt_index,
+ WCO_RLS_INSERT_CHECK,
+ merge_permissive_policies,
+ merge_restrictive_policies,
+ withCheckOptions,
+ hasSubLinks,
+ false);
+
+ /* Enforce the WITH CHECK clauses of the UPDATE policies */
+ add_with_check_options(rel, rt_index,
+ WCO_RLS_UPDATE_CHECK,
+ merge_permissive_policies,
+ merge_restrictive_policies,
+ withCheckOptions,
+ hasSubLinks,
+ false);
+ }
+
heap_close(rel, NoLock);
/*
@@ -438,6 +527,13 @@ get_policies_for_relation(Relation relation, CmdType cmd, Oid user_id,
if (policy->polcmd == ACL_DELETE_CHR)
cmd_matches = true;
break;
+ case CMD_MERGE:
+ /*
+ * We do not support a separate policy for MERGE command.
+ * Instead it derives from the policies defined for other
+ * commands.
+ */
+ break;
default:
elog(ERROR, "unrecognized policy command type %d",
(int) cmd);
diff --git a/src/backend/tcop/pquery.c b/src/backend/tcop/pquery.c
index 66cc5c3..50f852a 100644
--- a/src/backend/tcop/pquery.c
+++ b/src/backend/tcop/pquery.c
@@ -193,6 +193,11 @@ ProcessQuery(PlannedStmt *plan,
"DELETE " UINT64_FORMAT,
queryDesc->estate->es_processed);
break;
+ case CMD_MERGE:
+ snprintf(completionTag, COMPLETION_TAG_BUFSIZE,
+ "MERGE " UINT64_FORMAT,
+ queryDesc->estate->es_processed);
+ break;
default:
strcpy(completionTag, "???");
break;
diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index 3abe7d6..83e43dd 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -110,6 +110,7 @@ CommandIsReadOnly(PlannedStmt *pstmt)
case CMD_UPDATE:
case CMD_INSERT:
case CMD_DELETE:
+ case CMD_MERGE:
return false;
case CMD_UTILITY:
/* For now, treat all utility commands as read/write */
@@ -1847,6 +1848,8 @@ QueryReturnsTuples(Query *parsetree)
case CMD_SELECT:
/* returns tuples */
return true;
+ case CMD_MERGE:
+ return false;
case CMD_INSERT:
case CMD_UPDATE:
case CMD_DELETE:
@@ -2091,6 +2094,10 @@ CreateCommandTag(Node *parsetree)
tag = "UPDATE";
break;
+ case T_MergeStmt:
+ tag = "MERGE";
+ break;
+
case T_SelectStmt:
tag = "SELECT";
break;
@@ -2834,6 +2841,9 @@ CreateCommandTag(Node *parsetree)
case CMD_DELETE:
tag = "DELETE";
break;
+ case CMD_MERGE:
+ tag = "MERGE";
+ break;
case CMD_UTILITY:
tag = CreateCommandTag(stmt->utilityStmt);
break;
@@ -2894,6 +2904,9 @@ CreateCommandTag(Node *parsetree)
case CMD_DELETE:
tag = "DELETE";
break;
+ case CMD_MERGE:
+ tag = "MERGE";
+ break;
case CMD_UTILITY:
tag = CreateCommandTag(stmt->utilityStmt);
break;
@@ -2942,6 +2955,7 @@ GetCommandLogLevel(Node *parsetree)
case T_InsertStmt:
case T_DeleteStmt:
case T_UpdateStmt:
+ case T_MergeStmt:
lev = LOGSTMT_MOD;
break;
@@ -3381,6 +3395,7 @@ GetCommandLogLevel(Node *parsetree)
case CMD_UPDATE:
case CMD_INSERT:
case CMD_DELETE:
+ case CMD_MERGE:
lev = LOGSTMT_MOD;
break;
@@ -3411,6 +3426,7 @@ GetCommandLogLevel(Node *parsetree)
case CMD_UPDATE:
case CMD_INSERT:
case CMD_DELETE:
+ case CMD_MERGE:
lev = LOGSTMT_MOD;
break;
diff --git a/src/include/executor/spi.h b/src/include/executor/spi.h
index e5bdaec..78410b9 100644
--- a/src/include/executor/spi.h
+++ b/src/include/executor/spi.h
@@ -64,6 +64,7 @@ typedef struct _SPI_plan *SPIPlanPtr;
#define SPI_OK_REL_REGISTER 15
#define SPI_OK_REL_UNREGISTER 16
#define SPI_OK_TD_REGISTER 17
+#define SPI_OK_MERGE 18
#define SPI_OPT_NONATOMIC (1 << 0)
diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h
index a4574cd..dbfb5d2 100644
--- a/src/include/miscadmin.h
+++ b/src/include/miscadmin.h
@@ -444,5 +444,6 @@ extern bool has_rolreplication(Oid roleid);
/* in access/transam/xlog.c */
extern bool BackupInProgress(void);
extern void CancelBackup(void);
+extern int64 GetXactWALBytes(void);
#endif /* MISCADMIN_H */
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index 286d55b..bcbf01f 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -348,6 +348,7 @@ typedef struct JunkFilter
AttrNumber *jf_cleanMap;
TupleTableSlot *jf_resultSlot;
AttrNumber jf_junkAttNo;
+ AttrNumber jf_otherJunkAttNo;
} JunkFilter;
/*
@@ -426,6 +427,9 @@ typedef struct ResultRelInfo
/* relation descriptor for root partitioned table */
Relation ri_PartitionRoot;
+
+ /* RTI of the target relation for MERGE */
+ Index ri_mergeTargetRTI;
} ResultRelInfo;
/* ----------------
@@ -921,6 +925,13 @@ typedef struct PlanState
((PlanState *)(node))->instrument->nfiltered2 += (delta); \
} while(0)
+typedef enum EPQResult
+{
+ EPQ_UNUSED,
+ EPQ_TUPLE_IS_NULL,
+ EPQ_TUPLE_IS_NOT_NULL
+} EPQResult;
+
/*
* EPQState is state for executing an EvalPlanQual recheck on a candidate
* tuple in ModifyTable or LockRows. The estate and planstate fields are
@@ -934,6 +945,7 @@ typedef struct EPQState
Plan *plan; /* plan tree to be executed */
List *arowMarks; /* ExecAuxRowMarks (non-locking only) */
int epqParam; /* ID of Param to force scan node re-eval */
+ EPQResult epqresult; /* Result code used by MERGE */
} EPQState;
@@ -967,13 +979,28 @@ typedef struct ProjectSetState
} ProjectSetState;
/* ----------------
+ * MergeActionState information
+ * ----------------
+ */
+typedef struct MergeActionState
+{
+ NodeTag type;
+ bool matched; /* MATCHED or NOT MATCHED */
+ ExprState *whenqual; /* WHEN quals */
+ CmdType commandType; /* type of action */
+ Node *stmt; /* T_UpdateStmt etc */
+ TupleTableSlot *slot; /* instead of ResultRelInfo */
+ ProjectionInfo *proj; /* instead of ResultRelInfo */
+} MergeActionState;
+
+/* ----------------
* ModifyTableState information
* ----------------
*/
typedef struct ModifyTableState
{
PlanState ps; /* its first field is NodeTag */
- CmdType operation; /* INSERT, UPDATE, or DELETE */
+ CmdType operation; /* INSERT, UPDATE, DELETE or MERGE */
bool canSetTag; /* do we set the command tag/es_processed? */
bool mt_done; /* are we done? */
PlanState **mt_plans; /* subplans (one per target rel) */
@@ -999,6 +1026,10 @@ typedef struct ModifyTableState
/* controls transition table population for INSERT...ON CONFLICT UPDATE */
TupleConversionMap **mt_per_subplan_tupconv_maps;
/* Per plan map for tuple conversion from child to root */
+ TupleTableSlot **mt_merge_existing; /* extra slot for each subplan to
+ store existing tuple. */
+ List *mt_mergeActionStateLists; /* List of MERGE action states */
+ AclMode mt_merge_subcommands; /* Flags show which cmd types are present */
} ModifyTableState;
/* ----------------
diff --git a/src/include/nodes/nodes.h b/src/include/nodes/nodes.h
index 74b094a..8e960a8 100644
--- a/src/include/nodes/nodes.h
+++ b/src/include/nodes/nodes.h
@@ -96,6 +96,7 @@ typedef enum NodeTag
T_PlanState,
T_ResultState,
T_ProjectSetState,
+ T_MergeActionState,
T_ModifyTableState,
T_AppendState,
T_MergeAppendState,
@@ -307,6 +308,8 @@ typedef enum NodeTag
T_InsertStmt,
T_DeleteStmt,
T_UpdateStmt,
+ T_MergeStmt,
+ T_MergeAction,
T_SelectStmt,
T_AlterTableStmt,
T_AlterTableCmd,
@@ -656,7 +659,8 @@ typedef enum CmdType
CMD_SELECT, /* select stmt */
CMD_UPDATE, /* update stmt */
CMD_INSERT, /* insert stmt */
- CMD_DELETE,
+ CMD_DELETE, /* delete stmt */
+ CMD_MERGE, /* merge stmt */
CMD_UTILITY, /* cmds like create, destroy, copy, vacuum,
* etc. */
CMD_NOTHING /* dummy command for instead nothing rules
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index c7a43b8..68c4de3 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -38,7 +38,7 @@ typedef enum OverridingKind
typedef enum QuerySource
{
QSRC_ORIGINAL, /* original parsetree (explicit query) */
- QSRC_PARSER, /* added by parse analysis (now unused) */
+ QSRC_PARSER, /* added by parse analysis in MERGE */
QSRC_INSTEAD_RULE, /* added by unconditional INSTEAD rule */
QSRC_QUAL_INSTEAD_RULE, /* added by conditional INSTEAD rule */
QSRC_NON_INSTEAD_RULE /* added by non-INSTEAD rule */
@@ -107,7 +107,7 @@ typedef struct Query
{
NodeTag type;
- CmdType commandType; /* select|insert|update|delete|utility */
+ CmdType commandType; /* select|insert|update|delete|merge|utility */
QuerySource querySource; /* where did I come from? */
@@ -118,7 +118,7 @@ typedef struct Query
Node *utilityStmt; /* non-null if commandType == CMD_UTILITY */
int resultRelation; /* rtable index of target relation for
- * INSERT/UPDATE/DELETE; 0 for SELECT */
+ * INSERT/UPDATE/DELETE/MERGE; 0 for SELECT */
bool hasAggs; /* has aggregates in tlist or havingQual */
bool hasWindowFuncs; /* has window functions in tlist */
@@ -169,6 +169,9 @@ typedef struct Query
List *withCheckOptions; /* a list of WithCheckOption's, which are
* only added during rewrite and therefore
* are not written out as part of Query. */
+ int mergeTarget_relation;
+ List *mergeSourceTargetList;
+ List *mergeActionList; /* list of actions for MERGE (only) */
/*
* The following two fields identify the portion of the source text string
@@ -1127,7 +1130,9 @@ typedef enum WCOKind
WCO_VIEW_CHECK, /* WCO on an auto-updatable view */
WCO_RLS_INSERT_CHECK, /* RLS INSERT WITH CHECK policy */
WCO_RLS_UPDATE_CHECK, /* RLS UPDATE WITH CHECK policy */
- WCO_RLS_CONFLICT_CHECK /* RLS ON CONFLICT DO UPDATE USING policy */
+ WCO_RLS_CONFLICT_CHECK, /* RLS ON CONFLICT DO UPDATE USING policy */
+ WCO_RLS_MERGE_UPDATE_CHECK, /* RLS MERGE UPDATE USING policy */
+ WCO_RLS_MERGE_DELETE_CHECK /* RLS MERGE DELETE USING policy */
} WCOKind;
typedef struct WithCheckOption
@@ -1503,6 +1508,30 @@ typedef struct UpdateStmt
} UpdateStmt;
/* ----------------------
+ * Merge Statement
+ * ----------------------
+ */
+typedef struct MergeStmt
+{
+ NodeTag type;
+ RangeVar *relation; /* target relation to merge */
+ Node *source_relation;/* source relation */
+ Node *join_condition; /* join condition between source and target */
+ List *mergeActionList;/* list of MergeAction(s) */
+} MergeStmt;
+
+typedef struct MergeAction
+{
+ NodeTag type;
+ bool matched; /* MATCHED or NOT MATCHED */
+ Node *condition; /* conditional expr (raw parser) */
+ Node *qual; /* conditional expr (transformWhereClause) */
+ CmdType commandType; /* type of action */
+ Node *stmt; /* T_UpdateStmt etc - not planned */
+ List *targetList; /* the target list (of ResTarget) */
+} MergeAction;
+
+/* ----------------------
* Select Statement
*
* A "simple" SELECT is represented in the output of gram.y by a single
diff --git a/src/include/nodes/plannodes.h b/src/include/nodes/plannodes.h
index f2e19ea..7ba4c55 100644
--- a/src/include/nodes/plannodes.h
+++ b/src/include/nodes/plannodes.h
@@ -18,6 +18,7 @@
#include "lib/stringinfo.h"
#include "nodes/bitmapset.h"
#include "nodes/lockoptions.h"
+#include "nodes/parsenodes.h"
#include "nodes/primnodes.h"
@@ -42,7 +43,7 @@ typedef struct PlannedStmt
{
NodeTag type;
- CmdType commandType; /* select|insert|update|delete|utility */
+ CmdType commandType; /* select|insert|update|delete|merge|utility */
uint64 queryId; /* query identifier (copied from Query) */
@@ -214,13 +215,14 @@ typedef struct ProjectSet
typedef struct ModifyTable
{
Plan plan;
- CmdType operation; /* INSERT, UPDATE, or DELETE */
+ CmdType operation; /* INSERT, UPDATE, DELETE or MERGE */
bool canSetTag; /* do we set the command tag/es_processed? */
Index nominalRelation; /* Parent RT index for use of EXPLAIN */
/* RT indexes of non-leaf tables in a partition tree */
List *partitioned_rels;
bool partColsUpdated; /* some part key in hierarchy updated */
List *resultRelations; /* integer list of RT indexes */
+ List *mergeTargetRelations; /* integer list of RT indexes */
int resultRelIndex; /* index of first resultRel in plan's list */
int rootResultRelIndex; /* index of the partitioned table root */
List *plans; /* plan(s) producing source data */
@@ -236,6 +238,8 @@ typedef struct ModifyTable
Node *onConflictWhere; /* WHERE for ON CONFLICT UPDATE */
Index exclRelRTI; /* RTI of the EXCLUDED pseudo relation */
List *exclRelTlist; /* tlist of the EXCLUDED pseudo relation */
+ List *mergeSourceTargetLists;
+ List *mergeActionLists; /* actions for MERGE */
} ModifyTable;
/* ----------------
diff --git a/src/include/nodes/relation.h b/src/include/nodes/relation.h
index b1c6317..2258a58 100644
--- a/src/include/nodes/relation.h
+++ b/src/include/nodes/relation.h
@@ -1664,7 +1664,7 @@ typedef struct LockRowsPath
} LockRowsPath;
/*
- * ModifyTablePath represents performing INSERT/UPDATE/DELETE modifications
+ * ModifyTablePath represents performing INSERT/UPDATE/DELETE/MERGE
*
* We represent most things that will be in the ModifyTable plan node
* literally, except we have child Path(s) not Plan(s). But analysis of the
@@ -1673,13 +1673,14 @@ typedef struct LockRowsPath
typedef struct ModifyTablePath
{
Path path;
- CmdType operation; /* INSERT, UPDATE, or DELETE */
+ CmdType operation; /* INSERT, UPDATE, DELETE or MERGE */
bool canSetTag; /* do we set the command tag/es_processed? */
Index nominalRelation; /* Parent RT index for use of EXPLAIN */
/* RT indexes of non-leaf tables in a partition tree */
List *partitioned_rels;
bool partColsUpdated; /* some part key in hierarchy updated */
List *resultRelations; /* integer list of RT indexes */
+ List *mergeTargetRelations; /* integer list of RT indexes */
List *subpaths; /* Path(s) producing source data */
List *subroots; /* per-target-table PlannerInfos */
List *withCheckOptionLists; /* per-target-table WCO lists */
@@ -1687,6 +1688,8 @@ typedef struct ModifyTablePath
List *rowMarks; /* PlanRowMarks (non-locking only) */
OnConflictExpr *onconflict; /* ON CONFLICT clause, or NULL */
int epqParam; /* ID of Param for EvalPlanQual re-eval */
+ List *mergeSourceTargetLists;
+ List *mergeActionLists; /* actions for MERGE */
} ModifyTablePath;
/*
diff --git a/src/include/optimizer/pathnode.h b/src/include/optimizer/pathnode.h
index ef7173f..2513b09 100644
--- a/src/include/optimizer/pathnode.h
+++ b/src/include/optimizer/pathnode.h
@@ -243,11 +243,14 @@ extern ModifyTablePath *create_modifytable_path(PlannerInfo *root,
CmdType operation, bool canSetTag,
Index nominalRelation, List *partitioned_rels,
bool partColsUpdated,
- List *resultRelations, List *subpaths,
+ List *resultRelations,
+ List *mergeTargetRelations,
+ List *subpaths,
List *subroots,
List *withCheckOptionLists, List *returningLists,
List *rowMarks, OnConflictExpr *onconflict,
- int epqParam);
+ List *mergeSourceTargetList,
+ List *mergeActionList, int epqParam);
extern LimitPath *create_limit_path(PlannerInfo *root, RelOptInfo *rel,
Path *subpath,
Node *limitOffset, Node *limitCount,
diff --git a/src/include/parser/kwlist.h b/src/include/parser/kwlist.h
index cf32197..4dff55a 100644
--- a/src/include/parser/kwlist.h
+++ b/src/include/parser/kwlist.h
@@ -244,8 +244,10 @@ PG_KEYWORD("locked", LOCKED, UNRESERVED_KEYWORD)
PG_KEYWORD("logged", LOGGED, UNRESERVED_KEYWORD)
PG_KEYWORD("mapping", MAPPING, UNRESERVED_KEYWORD)
PG_KEYWORD("match", MATCH, UNRESERVED_KEYWORD)
+PG_KEYWORD("matched", MATCHED, UNRESERVED_KEYWORD)
PG_KEYWORD("materialized", MATERIALIZED, UNRESERVED_KEYWORD)
PG_KEYWORD("maxvalue", MAXVALUE, UNRESERVED_KEYWORD)
+PG_KEYWORD("merge", MERGE, UNRESERVED_KEYWORD)
PG_KEYWORD("method", METHOD, UNRESERVED_KEYWORD)
PG_KEYWORD("minute", MINUTE_P, UNRESERVED_KEYWORD)
PG_KEYWORD("minvalue", MINVALUE, UNRESERVED_KEYWORD)
diff --git a/src/include/parser/parse_clause.h b/src/include/parser/parse_clause.h
index 2c0e092..9a6b80a 100644
--- a/src/include/parser/parse_clause.h
+++ b/src/include/parser/parse_clause.h
@@ -17,10 +17,15 @@
#include "parser/parse_node.h"
extern void transformFromClause(ParseState *pstate, List *frmList);
+extern int transformMergeJoinClause(ParseState *pstate, Node *merge,
+ List **mergeSourceTargetList);
extern int setTargetTable(ParseState *pstate, RangeVar *relation,
bool inh, bool alsoSource, AclMode requiredPerms);
extern bool interpretOidsOption(List *defList, bool allowOids);
+extern void setNamespaceVisibilityForRTE(List *namespace, RangeTblEntry *rte,
+ bool rel_visible,
+ bool cols_visible);
extern Node *transformWhereClause(ParseState *pstate, Node *clause,
ParseExprKind exprKind, const char *constructName);
extern Node *transformLimitClause(ParseState *pstate, Node *clause,
diff --git a/src/include/parser/parse_node.h b/src/include/parser/parse_node.h
index 0230543..8b80e79 100644
--- a/src/include/parser/parse_node.h
+++ b/src/include/parser/parse_node.h
@@ -50,6 +50,7 @@ typedef enum ParseExprKind
EXPR_KIND_INSERT_TARGET, /* INSERT target list item */
EXPR_KIND_UPDATE_SOURCE, /* UPDATE assignment source item */
EXPR_KIND_UPDATE_TARGET, /* UPDATE assignment target item */
+ EXPR_KIND_MERGE_WHEN_AND, /* MERGE WHEN ... AND condition */
EXPR_KIND_GROUP_BY, /* GROUP BY */
EXPR_KIND_ORDER_BY, /* ORDER BY */
EXPR_KIND_DISTINCT_ON, /* DISTINCT ON */
@@ -127,7 +128,8 @@ typedef Node *(*CoerceParamHook) (ParseState *pstate, Param *param,
* p_parent_cte: CommonTableExpr that immediately contains the current query,
* if any.
*
- * p_target_relation: target relation, if query is INSERT, UPDATE, or DELETE.
+ * p_target_relation: target relation, if query is INSERT, UPDATE, DELETE
+ * or MERGE.
*
* p_target_rangetblentry: target relation's entry in the rtable list.
*
@@ -181,7 +183,7 @@ struct ParseState
List *p_ctenamespace; /* current namespace for common table exprs */
List *p_future_ctes; /* common table exprs not yet in namespace */
CommonTableExpr *p_parent_cte; /* this query's containing CTE */
- Relation p_target_relation; /* INSERT/UPDATE/DELETE target rel */
+ Relation p_target_relation; /* INSERT/UPDATE/DELETE/MERGE target rel */
RangeTblEntry *p_target_rangetblentry; /* target rel's RTE */
bool p_is_insert; /* process assignment like INSERT not UPDATE */
List *p_windowdefs; /* raw representations of window clauses */
diff --git a/src/include/rewrite/rewriteHandler.h b/src/include/rewrite/rewriteHandler.h
index 8128199..1ab5de3 100644
--- a/src/include/rewrite/rewriteHandler.h
+++ b/src/include/rewrite/rewriteHandler.h
@@ -25,6 +25,7 @@ extern void AcquireRewriteLocks(Query *parsetree,
extern Node *build_column_default(Relation rel, int attrno);
extern void rewriteTargetListUD(Query *parsetree, RangeTblEntry *target_rte,
Relation target_relation);
+extern void rewriteTargetListMerge(Query *parsetree, Relation target_relation);
extern Query *get_view_query(Relation view);
extern const char *view_query_is_auto_updatable(Query *viewquery,
diff --git a/src/interfaces/libpq/fe-exec.c b/src/interfaces/libpq/fe-exec.c
index 4c0114c..a432636 100644
--- a/src/interfaces/libpq/fe-exec.c
+++ b/src/interfaces/libpq/fe-exec.c
@@ -3055,9 +3055,9 @@ PQoidValue(const PGresult *res)
/*
* PQcmdTuples -
- * If the last command was INSERT/UPDATE/DELETE/MOVE/FETCH/COPY, return
- * a string containing the number of inserted/affected tuples. If not,
- * return "".
+ * If the last command was INSERT/UPDATE/DELETE/MERGE/MOVE/FETCH/COPY,
+ * return a string containing the number of inserted/affected tuples.
+ * If not, return "".
*
* XXX: this should probably return an int
*/
@@ -3084,7 +3084,8 @@ PQcmdTuples(PGresult *res)
strncmp(res->cmdStatus, "DELETE ", 7) == 0 ||
strncmp(res->cmdStatus, "UPDATE ", 7) == 0)
p = res->cmdStatus + 7;
- else if (strncmp(res->cmdStatus, "FETCH ", 6) == 0)
+ else if (strncmp(res->cmdStatus, "FETCH ", 6) == 0 ||
+ strncmp(res->cmdStatus, "MERGE ", 6) == 0)
p = res->cmdStatus + 6;
else if (strncmp(res->cmdStatus, "MOVE ", 5) == 0 ||
strncmp(res->cmdStatus, "COPY ", 5) == 0)
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 5054d20..1c8268a 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -3796,7 +3796,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
/*
* On the first call for this statement generate the plan, and detect
- * whether the statement is INSERT/UPDATE/DELETE
+ * whether the statement is INSERT/UPDATE/DELETE/MERGE
*/
if (expr->plan == NULL)
{
@@ -3817,6 +3817,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
{
if (q->commandType == CMD_INSERT ||
q->commandType == CMD_UPDATE ||
+ q->commandType == CMD_MERGE ||
q->commandType == CMD_DELETE)
stmt->mod_stmt = true;
}
@@ -3874,6 +3875,7 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
case SPI_OK_INSERT_RETURNING:
case SPI_OK_UPDATE_RETURNING:
case SPI_OK_DELETE_RETURNING:
+ case SPI_OK_MERGE:
Assert(stmt->mod_stmt);
exec_set_found(estate, (SPI_processed != 0));
break;
@@ -4051,6 +4053,7 @@ exec_stmt_dynexecute(PLpgSQL_execstate *estate,
case SPI_OK_INSERT_RETURNING:
case SPI_OK_UPDATE_RETURNING:
case SPI_OK_DELETE_RETURNING:
+ case SPI_OK_MERGE:
case SPI_OK_UTILITY:
case SPI_OK_REWRITTEN:
break;
diff --git a/src/pl/plpgsql/src/pl_gram.y b/src/pl/plpgsql/src/pl_gram.y
index 688fbd6..de6aa5a 100644
--- a/src/pl/plpgsql/src/pl_gram.y
+++ b/src/pl/plpgsql/src/pl_gram.y
@@ -301,6 +301,7 @@ static void check_raise_parameters(PLpgSQL_stmt_raise *stmt);
%token K_LAST
%token K_LOG
%token K_LOOP
+%token K_MERGE
%token K_MESSAGE
%token K_MESSAGE_TEXT
%token K_MOVE
@@ -1913,6 +1914,10 @@ stmt_execsql : K_IMPORT
{
$$ = make_execsql_stmt(K_INSERT, @1);
}
+ | K_MERGE
+ {
+ $$ = make_execsql_stmt(K_MERGE, @1);
+ }
| T_WORD
{
int tok;
@@ -2433,6 +2438,7 @@ unreserved_keyword :
| K_IS
| K_LAST
| K_LOG
+ | K_MERGE
| K_MESSAGE
| K_MESSAGE_TEXT
| K_MOVE
@@ -2894,6 +2900,8 @@ make_execsql_stmt(int firsttoken, int location)
{
if (prev_tok == K_INSERT)
continue; /* INSERT INTO is not an INTO-target */
+ if (prev_tok == K_MERGE)
+ continue; /* MERGE INTO is not an INTO-target */
if (firsttoken == K_IMPORT)
continue; /* IMPORT ... INTO is not an INTO-target */
if (have_into)
diff --git a/src/pl/plpgsql/src/pl_scanner.c b/src/pl/plpgsql/src/pl_scanner.c
index 12a3e6b..ad40824 100644
--- a/src/pl/plpgsql/src/pl_scanner.c
+++ b/src/pl/plpgsql/src/pl_scanner.c
@@ -136,6 +136,7 @@ static const ScanKeyword unreserved_keywords[] = {
PG_KEYWORD("is", K_IS, UNRESERVED_KEYWORD)
PG_KEYWORD("last", K_LAST, UNRESERVED_KEYWORD)
PG_KEYWORD("log", K_LOG, UNRESERVED_KEYWORD)
+ PG_KEYWORD("merge", K_MERGE, UNRESERVED_KEYWORD)
PG_KEYWORD("message", K_MESSAGE, UNRESERVED_KEYWORD)
PG_KEYWORD("message_text", K_MESSAGE_TEXT, UNRESERVED_KEYWORD)
PG_KEYWORD("move", K_MOVE, UNRESERVED_KEYWORD)
diff --git a/src/pl/plpgsql/src/plpgsql.h b/src/pl/plpgsql/src/plpgsql.h
index c2449f0..3843b79 100644
--- a/src/pl/plpgsql/src/plpgsql.h
+++ b/src/pl/plpgsql/src/plpgsql.h
@@ -833,8 +833,8 @@ typedef struct PLpgSQL_stmt_execsql
PLpgSQL_stmt_type cmd_type;
int lineno;
PLpgSQL_expr *sqlstmt;
- bool mod_stmt; /* is the stmt INSERT/UPDATE/DELETE? Note:
- * mod_stmt is set when we plan the query */
+ bool mod_stmt; /* is the stmt INSERT/UPDATE/DELETE/MERGE?
+ * Note mod_stmt is set when we plan the query */
bool into; /* INTO supplied? */
bool strict; /* INTO STRICT flag */
PLpgSQL_variable *target; /* INTO target (record or row) */
diff --git a/src/test/isolation/expected/merge-delete.out b/src/test/isolation/expected/merge-delete.out
new file mode 100644
index 0000000..1cb09f0
--- /dev/null
+++ b/src/test/isolation/expected/merge-delete.out
@@ -0,0 +1,95 @@
+Parsed test spec with 2 sessions
+
+starting permutation: delete c1 select2 c2
+step delete: DELETE FROM target t WHERE t.key = 1;
+step c1: COMMIT;
+step select2: SELECT * FROM target;
+key val
+
+step c2: COMMIT;
+
+starting permutation: merge_delete c1 select2 c2
+step merge_delete: MERGE INTO target t USING (SELECT 1 as key) s ON s.key = t.key WHEN MATCHED THEN DELETE;
+step c1: COMMIT;
+step select2: SELECT * FROM target;
+key val
+
+step c2: COMMIT;
+
+starting permutation: delete c1 update1 select2 c2
+step delete: DELETE FROM target t WHERE t.key = 1;
+step c1: COMMIT;
+step update1: UPDATE target t SET val = t.val || ' updated by update1' WHERE t.key = 1;
+step select2: SELECT * FROM target;
+key val
+
+step c2: COMMIT;
+
+starting permutation: merge_delete c1 update1 select2 c2
+step merge_delete: MERGE INTO target t USING (SELECT 1 as key) s ON s.key = t.key WHEN MATCHED THEN DELETE;
+step c1: COMMIT;
+step update1: UPDATE target t SET val = t.val || ' updated by update1' WHERE t.key = 1;
+step select2: SELECT * FROM target;
+key val
+
+step c2: COMMIT;
+
+starting permutation: delete c1 merge2 select2 c2
+step delete: DELETE FROM target t WHERE t.key = 1;
+step c1: COMMIT;
+step merge2: MERGE INTO target t USING (SELECT 1 as key, 'merge2a' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+step select2: SELECT * FROM target;
+key val
+
+1 merge2a
+step c2: COMMIT;
+
+starting permutation: merge_delete c1 merge2 select2 c2
+step merge_delete: MERGE INTO target t USING (SELECT 1 as key) s ON s.key = t.key WHEN MATCHED THEN DELETE;
+step c1: COMMIT;
+step merge2: MERGE INTO target t USING (SELECT 1 as key, 'merge2a' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+step select2: SELECT * FROM target;
+key val
+
+1 merge2a
+step c2: COMMIT;
+
+starting permutation: delete update1 c1 select2 c2
+step delete: DELETE FROM target t WHERE t.key = 1;
+step update1: UPDATE target t SET val = t.val || ' updated by update1' WHERE t.key = 1;
+step c1: COMMIT;
+step update1: <... completed>
+step select2: SELECT * FROM target;
+key val
+
+step c2: COMMIT;
+
+starting permutation: merge_delete update1 c1 select2 c2
+step merge_delete: MERGE INTO target t USING (SELECT 1 as key) s ON s.key = t.key WHEN MATCHED THEN DELETE;
+step update1: UPDATE target t SET val = t.val || ' updated by update1' WHERE t.key = 1;
+step c1: COMMIT;
+step update1: <... completed>
+step select2: SELECT * FROM target;
+key val
+
+step c2: COMMIT;
+
+starting permutation: delete merge2 c1 select2 c2
+step delete: DELETE FROM target t WHERE t.key = 1;
+step merge2: MERGE INTO target t USING (SELECT 1 as key, 'merge2a' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+step c1: COMMIT;
+step merge2: <... completed>
+error in steps c1 merge2: ERROR: could not serialize access due to concurrent update
+step select2: SELECT * FROM target;
+ERROR: current transaction is aborted, commands ignored until end of transaction block
+step c2: COMMIT;
+
+starting permutation: merge_delete merge2 c1 select2 c2
+step merge_delete: MERGE INTO target t USING (SELECT 1 as key) s ON s.key = t.key WHEN MATCHED THEN DELETE;
+step merge2: MERGE INTO target t USING (SELECT 1 as key, 'merge2a' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+step c1: COMMIT;
+step merge2: <... completed>
+error in steps c1 merge2: ERROR: could not serialize access due to concurrent update
+step select2: SELECT * FROM target;
+ERROR: current transaction is aborted, commands ignored until end of transaction block
+step c2: COMMIT;
diff --git a/src/test/isolation/expected/merge-insert-update.out b/src/test/isolation/expected/merge-insert-update.out
new file mode 100644
index 0000000..317fa16
--- /dev/null
+++ b/src/test/isolation/expected/merge-insert-update.out
@@ -0,0 +1,84 @@
+Parsed test spec with 2 sessions
+
+starting permutation: merge1 c1 select2 c2
+step merge1: MERGE INTO target t USING (SELECT 1 as key, 'merge1' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge1';
+step c1: COMMIT;
+step select2: SELECT * FROM target;
+key val
+
+1 merge1
+step c2: COMMIT;
+
+starting permutation: merge1 c1 merge2 select2 c2
+step merge1: MERGE INTO target t USING (SELECT 1 as key, 'merge1' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge1';
+step c1: COMMIT;
+step merge2: MERGE INTO target t USING (SELECT 1 as key, 'merge2' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge2';
+step select2: SELECT * FROM target;
+key val
+
+1 merge1 updated by merge2
+step c2: COMMIT;
+
+starting permutation: insert1 merge2 c1 select2 c2
+step insert1: INSERT INTO target VALUES (1, 'insert1');
+step merge2: MERGE INTO target t USING (SELECT 1 as key, 'merge2' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge2';
+step c1: COMMIT;
+step merge2: <... completed>
+error in steps c1 merge2: ERROR: duplicate key value violates unique constraint "target_pkey"
+step select2: SELECT * FROM target;
+ERROR: current transaction is aborted, commands ignored until end of transaction block
+step c2: COMMIT;
+
+starting permutation: merge1 merge2 c1 select2 c2
+step merge1: MERGE INTO target t USING (SELECT 1 as key, 'merge1' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge1';
+step merge2: MERGE INTO target t USING (SELECT 1 as key, 'merge2' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge2';
+step c1: COMMIT;
+step merge2: <... completed>
+error in steps c1 merge2: ERROR: duplicate key value violates unique constraint "target_pkey"
+step select2: SELECT * FROM target;
+ERROR: current transaction is aborted, commands ignored until end of transaction block
+step c2: COMMIT;
+
+starting permutation: merge1 merge2 a1 select2 c2
+step merge1: MERGE INTO target t USING (SELECT 1 as key, 'merge1' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge1';
+step merge2: MERGE INTO target t USING (SELECT 1 as key, 'merge2' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge2';
+step a1: ABORT;
+step merge2: <... completed>
+step select2: SELECT * FROM target;
+key val
+
+1 merge2
+step c2: COMMIT;
+
+starting permutation: delete1 insert1 c1 merge2 select2 c2
+step delete1: DELETE FROM target WHERE key = 1;
+step insert1: INSERT INTO target VALUES (1, 'insert1');
+step c1: COMMIT;
+step merge2: MERGE INTO target t USING (SELECT 1 as key, 'merge2' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge2';
+step select2: SELECT * FROM target;
+key val
+
+1 insert1 updated by merge2
+step c2: COMMIT;
+
+starting permutation: delete1 insert1 merge2 c1 select2 c2
+step delete1: DELETE FROM target WHERE key = 1;
+step insert1: INSERT INTO target VALUES (1, 'insert1');
+step merge2: MERGE INTO target t USING (SELECT 1 as key, 'merge2' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge2';
+step c1: COMMIT;
+step merge2: <... completed>
+error in steps c1 merge2: ERROR: duplicate key value violates unique constraint "target_pkey"
+step select2: SELECT * FROM target;
+ERROR: current transaction is aborted, commands ignored until end of transaction block
+step c2: COMMIT;
+
+starting permutation: delete1 insert1 merge2i c1 select2 c2
+step delete1: DELETE FROM target WHERE key = 1;
+step insert1: INSERT INTO target VALUES (1, 'insert1');
+step merge2i: MERGE INTO target t USING (SELECT 1 as key, 'merge2' as val) s ON s.key = t.key WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge2';
+step c1: COMMIT;
+step select2: SELECT * FROM target;
+key val
+
+1 insert1
+step c2: COMMIT;
diff --git a/src/test/isolation/expected/merge-match-recheck.out b/src/test/isolation/expected/merge-match-recheck.out
new file mode 100644
index 0000000..96a9f45
--- /dev/null
+++ b/src/test/isolation/expected/merge-match-recheck.out
@@ -0,0 +1,106 @@
+Parsed test spec with 2 sessions
+
+starting permutation: update1 merge_status c2 select1 c1
+step update1: UPDATE target t SET balance = balance + 10, val = t.val || ' updated by update1' WHERE t.key = 1;
+step merge_status:
+ MERGE INTO target t
+ USING (SELECT 1 as key) s
+ ON s.key = t.key
+ WHEN MATCHED AND status = 's1' THEN
+ UPDATE SET status = 's2', val = t.val || ' when1'
+ WHEN MATCHED AND status = 's2' THEN
+ UPDATE SET status = 's3', val = t.val || ' when2'
+ WHEN MATCHED AND status = 's3' THEN
+ UPDATE SET status = 's4', val = t.val || ' when3';
+
+step c2: COMMIT;
+step merge_status: <... completed>
+step select1: SELECT * FROM target;
+key balance status val
+
+1 170 s2 setup updated by update1 when1
+step c1: COMMIT;
+
+starting permutation: update2 merge_status c2 select1 c1
+step update2: UPDATE target t SET status = 's2', val = t.val || ' updated by update2' WHERE t.key = 1;
+step merge_status:
+ MERGE INTO target t
+ USING (SELECT 1 as key) s
+ ON s.key = t.key
+ WHEN MATCHED AND status = 's1' THEN
+ UPDATE SET status = 's2', val = t.val || ' when1'
+ WHEN MATCHED AND status = 's2' THEN
+ UPDATE SET status = 's3', val = t.val || ' when2'
+ WHEN MATCHED AND status = 's3' THEN
+ UPDATE SET status = 's4', val = t.val || ' when3';
+
+step c2: COMMIT;
+step merge_status: <... completed>
+step select1: SELECT * FROM target;
+key balance status val
+
+1 160 s3 setup updated by update2 when2
+step c1: COMMIT;
+
+starting permutation: update3 merge_status c2 select1 c1
+step update3: UPDATE target t SET status = 's3', val = t.val || ' updated by update3' WHERE t.key = 1;
+step merge_status:
+ MERGE INTO target t
+ USING (SELECT 1 as key) s
+ ON s.key = t.key
+ WHEN MATCHED AND status = 's1' THEN
+ UPDATE SET status = 's2', val = t.val || ' when1'
+ WHEN MATCHED AND status = 's2' THEN
+ UPDATE SET status = 's3', val = t.val || ' when2'
+ WHEN MATCHED AND status = 's3' THEN
+ UPDATE SET status = 's4', val = t.val || ' when3';
+
+step c2: COMMIT;
+step merge_status: <... completed>
+step select1: SELECT * FROM target;
+key balance status val
+
+1 160 s4 setup updated by update3 when3
+step c1: COMMIT;
+
+starting permutation: update5 merge_status c2 select1 c1
+step update5: UPDATE target t SET status = 's5', val = t.val || ' updated by update5' WHERE t.key = 1;
+step merge_status:
+ MERGE INTO target t
+ USING (SELECT 1 as key) s
+ ON s.key = t.key
+ WHEN MATCHED AND status = 's1' THEN
+ UPDATE SET status = 's2', val = t.val || ' when1'
+ WHEN MATCHED AND status = 's2' THEN
+ UPDATE SET status = 's3', val = t.val || ' when2'
+ WHEN MATCHED AND status = 's3' THEN
+ UPDATE SET status = 's4', val = t.val || ' when3';
+
+step c2: COMMIT;
+step merge_status: <... completed>
+step select1: SELECT * FROM target;
+key balance status val
+
+1 160 s5 setup updated by update5
+step c1: COMMIT;
+
+starting permutation: update_bal1 merge_bal c2 select1 c1
+step update_bal1: UPDATE target t SET balance = 50, val = t.val || ' updated by update_bal1' WHERE t.key = 1;
+step merge_bal:
+ MERGE INTO target t
+ USING (SELECT 1 as key) s
+ ON s.key = t.key
+ WHEN MATCHED AND balance < 100 THEN
+ UPDATE SET balance = balance * 2, val = t.val || ' when1'
+ WHEN MATCHED AND balance < 200 THEN
+ UPDATE SET balance = balance * 4, val = t.val || ' when2'
+ WHEN MATCHED AND balance < 300 THEN
+ UPDATE SET balance = balance * 8, val = t.val || ' when3';
+
+step c2: COMMIT;
+step merge_bal: <... completed>
+step select1: SELECT * FROM target;
+key balance status val
+
+1 100 s1 setup updated by update_bal1 when1
+step c1: COMMIT;
diff --git a/src/test/isolation/expected/merge-update.out b/src/test/isolation/expected/merge-update.out
new file mode 100644
index 0000000..7186ede
--- /dev/null
+++ b/src/test/isolation/expected/merge-update.out
@@ -0,0 +1,204 @@
+Parsed test spec with 2 sessions
+
+starting permutation: merge1 c1 select2 c2
+step merge1:
+ MERGE INTO target t
+ USING (SELECT 1 as key, 'merge1' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+
+step c1: COMMIT;
+step select2: SELECT * FROM target;
+key val
+
+2 setup1 updated by merge1
+step c2: COMMIT;
+
+starting permutation: merge1 c1 merge2a select2 c2
+step merge1:
+ MERGE INTO target t
+ USING (SELECT 1 as key, 'merge1' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+
+step c1: COMMIT;
+step merge2a:
+ MERGE INTO target t
+ USING (SELECT 1 as key, 'merge2a' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+
+step select2: SELECT * FROM target;
+key val
+
+2 setup1 updated by merge1
+1 merge2a
+step c2: COMMIT;
+
+starting permutation: merge1 merge2a c1 select2 c2
+step merge1:
+ MERGE INTO target t
+ USING (SELECT 1 as key, 'merge1' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+
+step merge2a:
+ MERGE INTO target t
+ USING (SELECT 1 as key, 'merge2a' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+
+step c1: COMMIT;
+step merge2a: <... completed>
+error in steps c1 merge2a: ERROR: could not serialize access due to concurrent update
+step select2: SELECT * FROM target;
+ERROR: current transaction is aborted, commands ignored until end of transaction block
+step c2: COMMIT;
+
+starting permutation: merge1 merge2a a1 select2 c2
+step merge1:
+ MERGE INTO target t
+ USING (SELECT 1 as key, 'merge1' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+
+step merge2a:
+ MERGE INTO target t
+ USING (SELECT 1 as key, 'merge2a' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+
+step a1: ABORT;
+step merge2a: <... completed>
+step select2: SELECT * FROM target;
+key val
+
+2 setup1 updated by merge2a
+step c2: COMMIT;
+
+starting permutation: merge1 merge2b c1 select2 c2
+step merge1:
+ MERGE INTO target t
+ USING (SELECT 1 as key, 'merge1' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+
+step merge2b:
+ MERGE INTO target t
+ USING (SELECT 1 as key, 'merge2b' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED AND t.key < 2 THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+
+step c1: COMMIT;
+step merge2b: <... completed>
+error in steps c1 merge2b: ERROR: could not serialize access due to concurrent update
+step select2: SELECT * FROM target;
+ERROR: current transaction is aborted, commands ignored until end of transaction block
+step c2: COMMIT;
+
+starting permutation: merge1 merge2c c1 select2 c2
+step merge1:
+ MERGE INTO target t
+ USING (SELECT 1 as key, 'merge1' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+
+step merge2c:
+ MERGE INTO target t
+ USING (SELECT 1 as key, 'merge2c' as val) s
+ ON s.key = t.key AND t.key < 2
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+
+step c1: COMMIT;
+step merge2c: <... completed>
+error in steps c1 merge2c: ERROR: could not serialize access due to concurrent update
+step select2: SELECT * FROM target;
+ERROR: current transaction is aborted, commands ignored until end of transaction block
+step c2: COMMIT;
+
+starting permutation: pa_merge1 pa_merge2a c1 pa_select2 c2
+step pa_merge1:
+ MERGE INTO pa_target t
+ USING (SELECT 1 as key, 'pa_merge1' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set val = t.val || ' updated by ' || s.val;
+
+step pa_merge2a:
+ MERGE INTO pa_target t
+ USING (SELECT 1 as key, 'pa_merge2a' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+
+step c1: COMMIT;
+step pa_merge2a: <... completed>
+step pa_select2: SELECT * FROM pa_target;
+key val
+
+2 initial
+2 initial updated by pa_merge2a
+step c2: COMMIT;
+
+starting permutation: pa_merge2 pa_merge2a c1 pa_select2 c2
+step pa_merge2:
+ MERGE INTO pa_target t
+ USING (SELECT 1 as key, 'pa_merge1' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+
+step pa_merge2a:
+ MERGE INTO pa_target t
+ USING (SELECT 1 as key, 'pa_merge2a' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+
+step c1: COMMIT;
+step pa_merge2a: <... completed>
+error in steps c1 pa_merge2a: ERROR: could not serialize access due to concurrent update
+step pa_select2: SELECT * FROM pa_target;
+ERROR: current transaction is aborted, commands ignored until end of transaction block
+step c2: COMMIT;
diff --git a/src/test/isolation/isolation_schedule b/src/test/isolation/isolation_schedule
index 74d7d59..644e071 100644
--- a/src/test/isolation/isolation_schedule
+++ b/src/test/isolation/isolation_schedule
@@ -33,6 +33,10 @@ test: insert-conflict-do-update
test: insert-conflict-do-update-2
test: insert-conflict-do-update-3
test: insert-conflict-toast
+test: merge-insert-update
+test: merge-delete
+test: merge-update
+test: merge-match-recheck
test: delete-abort-savept
test: delete-abort-savept-2
test: aborted-keyrevoke
diff --git a/src/test/isolation/specs/merge-delete.spec b/src/test/isolation/specs/merge-delete.spec
new file mode 100644
index 0000000..656954f
--- /dev/null
+++ b/src/test/isolation/specs/merge-delete.spec
@@ -0,0 +1,51 @@
+# MERGE DELETE
+#
+# This test looks at the interactions involving concurrent deletes
+# comparing the behavior of MERGE, DELETE and UPDATE
+
+setup
+{
+ CREATE TABLE target (key int primary key, val text);
+ INSERT INTO target VALUES (1, 'setup1');
+}
+
+teardown
+{
+ DROP TABLE target;
+}
+
+session "s1"
+setup
+{
+ BEGIN ISOLATION LEVEL READ COMMITTED;
+}
+step "delete" { DELETE FROM target t WHERE t.key = 1; }
+step "merge_delete" { MERGE INTO target t USING (SELECT 1 as key) s ON s.key = t.key WHEN MATCHED THEN DELETE; }
+step "c1" { COMMIT; }
+step "a1" { ABORT; }
+
+session "s2"
+setup
+{
+ BEGIN ISOLATION LEVEL READ COMMITTED;
+}
+step "update1" { UPDATE target t SET val = t.val || ' updated by update1' WHERE t.key = 1; }
+step "merge2" { MERGE INTO target t USING (SELECT 1 as key, 'merge2a' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val; }
+step "select2" { SELECT * FROM target; }
+step "c2" { COMMIT; }
+
+# Basic effects
+permutation "delete" "c1" "select2" "c2"
+permutation "merge_delete" "c1" "select2" "c2"
+
+# One after the other, no concurrency
+permutation "delete" "c1" "update1" "select2" "c2"
+permutation "merge_delete" "c1" "update1" "select2" "c2"
+permutation "delete" "c1" "merge2" "select2" "c2"
+permutation "merge_delete" "c1" "merge2" "select2" "c2"
+
+# Now with concurrency
+permutation "delete" "update1" "c1" "select2" "c2"
+permutation "merge_delete" "update1" "c1" "select2" "c2"
+permutation "delete" "merge2" "c1" "select2" "c2"
+permutation "merge_delete" "merge2" "c1" "select2" "c2"
diff --git a/src/test/isolation/specs/merge-insert-update.spec b/src/test/isolation/specs/merge-insert-update.spec
new file mode 100644
index 0000000..704492b
--- /dev/null
+++ b/src/test/isolation/specs/merge-insert-update.spec
@@ -0,0 +1,52 @@
+# MERGE INSERT UPDATE
+#
+# This looks at how we handle concurrent INSERTs, illustrating how the
+# behavior differs from INSERT ... ON CONFLICT
+
+setup
+{
+ CREATE TABLE target (key int primary key, val text);
+}
+
+teardown
+{
+ DROP TABLE target;
+}
+
+session "s1"
+setup
+{
+ BEGIN ISOLATION LEVEL READ COMMITTED;
+}
+step "merge1" { MERGE INTO target t USING (SELECT 1 as key, 'merge1' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge1'; }
+step "delete1" { DELETE FROM target WHERE key = 1; }
+step "insert1" { INSERT INTO target VALUES (1, 'insert1'); }
+step "c1" { COMMIT; }
+step "a1" { ABORT; }
+
+session "s2"
+setup
+{
+ BEGIN ISOLATION LEVEL READ COMMITTED;
+}
+step "merge2" { MERGE INTO target t USING (SELECT 1 as key, 'merge2' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge2'; }
+
+step "merge2i" { MERGE INTO target t USING (SELECT 1 as key, 'merge2' as val) s ON s.key = t.key WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge2'; }
+
+step "select2" { SELECT * FROM target; }
+step "c2" { COMMIT; }
+step "a2" { ABORT; }
+
+# Basic effects
+permutation "merge1" "c1" "select2" "c2"
+permutation "merge1" "c1" "merge2" "select2" "c2"
+
+# check concurrent inserts
+permutation "insert1" "merge2" "c1" "select2" "c2"
+permutation "merge1" "merge2" "c1" "select2" "c2"
+permutation "merge1" "merge2" "a1" "select2" "c2"
+
+# check how we handle when visible row has been concurrently deleted, then same key re-inserted
+permutation "delete1" "insert1" "c1" "merge2" "select2" "c2"
+permutation "delete1" "insert1" "merge2" "c1" "select2" "c2"
+permutation "delete1" "insert1" "merge2i" "c1" "select2" "c2"
diff --git a/src/test/isolation/specs/merge-match-recheck.spec b/src/test/isolation/specs/merge-match-recheck.spec
new file mode 100644
index 0000000..193033d
--- /dev/null
+++ b/src/test/isolation/specs/merge-match-recheck.spec
@@ -0,0 +1,79 @@
+# MERGE MATCHED RECHECK
+#
+# This test looks at what happens when we have complex
+# WHEN MATCHED AND conditions and a concurrent UPDATE causes a
+# recheck of the AND condition on the new row
+
+setup
+{
+ CREATE TABLE target (key int primary key, balance integer, status text, val text);
+ INSERT INTO target VALUES (1, 160, 's1', 'setup');
+}
+
+teardown
+{
+ DROP TABLE target;
+}
+
+session "s1"
+setup
+{
+ BEGIN ISOLATION LEVEL READ COMMITTED;
+}
+step "merge_status"
+{
+ MERGE INTO target t
+ USING (SELECT 1 as key) s
+ ON s.key = t.key
+ WHEN MATCHED AND status = 's1' THEN
+ UPDATE SET status = 's2', val = t.val || ' when1'
+ WHEN MATCHED AND status = 's2' THEN
+ UPDATE SET status = 's3', val = t.val || ' when2'
+ WHEN MATCHED AND status = 's3' THEN
+ UPDATE SET status = 's4', val = t.val || ' when3';
+}
+
+step "merge_bal"
+{
+ MERGE INTO target t
+ USING (SELECT 1 as key) s
+ ON s.key = t.key
+ WHEN MATCHED AND balance < 100 THEN
+ UPDATE SET balance = balance * 2, val = t.val || ' when1'
+ WHEN MATCHED AND balance < 200 THEN
+ UPDATE SET balance = balance * 4, val = t.val || ' when2'
+ WHEN MATCHED AND balance < 300 THEN
+ UPDATE SET balance = balance * 8, val = t.val || ' when3';
+}
+
+step "select1" { SELECT * FROM target; }
+step "c1" { COMMIT; }
+step "a1" { ABORT; }
+
+session "s2"
+setup
+{
+ BEGIN ISOLATION LEVEL READ COMMITTED;
+}
+step "update1" { UPDATE target t SET balance = balance + 10, val = t.val || ' updated by update1' WHERE t.key = 1; }
+step "update2" { UPDATE target t SET status = 's2', val = t.val || ' updated by update2' WHERE t.key = 1; }
+step "update3" { UPDATE target t SET status = 's3', val = t.val || ' updated by update3' WHERE t.key = 1; }
+step "update5" { UPDATE target t SET status = 's5', val = t.val || ' updated by update5' WHERE t.key = 1; }
+step "update_bal1" { UPDATE target t SET balance = 50, val = t.val || ' updated by update_bal1' WHERE t.key = 1; }
+step "select2" { SELECT * FROM target; }
+step "c2" { COMMIT; }
+
+# merge_status sees concurrently updated row and rechecks WHEN conditions, but recheck passes and final status = 's2'
+permutation "update1" "merge_status" "c2" "select1" "c1"
+
+# merge_status sees concurrently updated row and rechecks WHEN conditions, recheck fails, so final status = 's3' not 's2'
+permutation "update2" "merge_status" "c2" "select1" "c1"
+
+# merge_status sees concurrently updated row and rechecks WHEN conditions, recheck fails, so final status = 's4' not 's2'
+permutation "update3" "merge_status" "c2" "select1" "c1"
+
+# merge_status sees concurrently updated row and rechecks WHEN conditions, recheck fails, but we skip update and MERGE does nothing
+permutation "update5" "merge_status" "c2" "select1" "c1"
+
+# merge_bal sees concurrently updated row and rechecks WHEN conditions, recheck fails, so final balance = 100 not 640
+permutation "update_bal1" "merge_bal" "c2" "select1" "c1"
diff --git a/src/test/isolation/specs/merge-update.spec b/src/test/isolation/specs/merge-update.spec
new file mode 100644
index 0000000..af7c9b6
--- /dev/null
+++ b/src/test/isolation/specs/merge-update.spec
@@ -0,0 +1,132 @@
+# MERGE UPDATE
+#
+# This test exercises atypical cases
+# 1. UPDATEs of PKs that change the join in the ON clause
+# 2. UPDATEs with WHEN AND conditions that would fail after concurrent update
+# 3. UPDATEs with extra ON conditions that would fail after concurrent update
+
+setup
+{
+ CREATE TABLE target (key int primary key, val text);
+ INSERT INTO target VALUES (1, 'setup1');
+
+ CREATE TABLE pa_target (key integer, val text)
+ PARTITION BY LIST (key);
+ CREATE TABLE part1 (key integer, val text);
+ CREATE TABLE part2 (val text, key integer);
+ CREATE TABLE part3 (key integer, val text);
+
+ ALTER TABLE pa_target ATTACH PARTITION part1 FOR VALUES IN (1,4);
+ ALTER TABLE pa_target ATTACH PARTITION part2 FOR VALUES IN (2,5,6);
+ ALTER TABLE pa_target ATTACH PARTITION part3 DEFAULT;
+
+ INSERT INTO pa_target VALUES (1, 'initial');
+ INSERT INTO pa_target VALUES (2, 'initial');
+}
+
+teardown
+{
+ DROP TABLE target;
+ DROP TABLE pa_target CASCADE;
+}
+
+session "s1"
+setup
+{
+ BEGIN ISOLATION LEVEL READ COMMITTED;
+}
+step "merge1"
+{
+ MERGE INTO target t
+ USING (SELECT 1 as key, 'merge1' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+}
+step "pa_merge1"
+{
+ MERGE INTO pa_target t
+ USING (SELECT 1 as key, 'pa_merge1' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set val = t.val || ' updated by ' || s.val;
+}
+step "pa_merge2"
+{
+ MERGE INTO pa_target t
+ USING (SELECT 1 as key, 'pa_merge1' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+}
+step "c1" { COMMIT; }
+step "a1" { ABORT; }
+
+session "s2"
+setup
+{
+ BEGIN ISOLATION LEVEL READ COMMITTED;
+}
+step "merge2a"
+{
+ MERGE INTO target t
+ USING (SELECT 1 as key, 'merge2a' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+}
+step "merge2b"
+{
+ MERGE INTO target t
+ USING (SELECT 1 as key, 'merge2b' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED AND t.key < 2 THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+}
+step "merge2c"
+{
+ MERGE INTO target t
+ USING (SELECT 1 as key, 'merge2c' as val) s
+ ON s.key = t.key AND t.key < 2
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+}
+step "pa_merge2a"
+{
+ MERGE INTO pa_target t
+ USING (SELECT 1 as key, 'pa_merge2a' as val) s
+ ON s.key = t.key
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (s.key, s.val)
+ WHEN MATCHED THEN
+ UPDATE set key = t.key + 1, val = t.val || ' updated by ' || s.val;
+}
+step "select2" { SELECT * FROM target; }
+step "pa_select2" { SELECT * FROM pa_target; }
+step "c2" { COMMIT; }
+
+# Basic effects
+permutation "merge1" "c1" "select2" "c2"
+
+# One after the other, no concurrency
+permutation "merge1" "c1" "merge2a" "select2" "c2"
+
+# Now with concurrency
+permutation "merge1" "merge2a" "c1" "select2" "c2"
+permutation "merge1" "merge2a" "a1" "select2" "c2"
+permutation "merge1" "merge2b" "c1" "select2" "c2"
+permutation "merge1" "merge2c" "c1" "select2" "c2"
+permutation "pa_merge1" "pa_merge2a" "c1" "pa_select2" "c2"
+permutation "pa_merge2" "pa_merge2a" "c1" "pa_select2" "c2"
diff --git a/src/test/regress/expected/identity.out b/src/test/regress/expected/identity.out
index 5536044..571f19f 100644
--- a/src/test/regress/expected/identity.out
+++ b/src/test/regress/expected/identity.out
@@ -386,3 +386,58 @@ CREATE TABLE itest_child PARTITION OF itest_parent (
) FOR VALUES FROM ('2016-07-01') TO ('2016-08-01'); -- error
ERROR: identity columns are not supported on partitions
DROP TABLE itest_parent;
+-- MERGE tests
+CREATE TABLE itest14 (a int GENERATED ALWAYS AS IDENTITY, b text);
+CREATE TABLE itest15 (a int GENERATED BY DEFAULT AS IDENTITY, b text);
+MERGE INTO itest14 t
+USING (SELECT 10 AS s_a, 'inserted by merge' AS s_b) s
+ON t.a = s.s_a
+WHEN NOT MATCHED THEN
+ INSERT (a, b) VALUES (s.s_a, s.s_b);
+ERROR: cannot insert into column "a"
+DETAIL: Column "a" is an identity column defined as GENERATED ALWAYS.
+HINT: Use OVERRIDING SYSTEM VALUE to override.
+MERGE INTO itest14 t
+USING (SELECT 20 AS s_a, 'inserted by merge' AS s_b) s
+ON t.a = s.s_a
+WHEN NOT MATCHED THEN
+ INSERT (a, b) OVERRIDING USER VALUE VALUES (s.s_a, s.s_b);
+ERROR: cannot insert into column "a"
+DETAIL: Column "a" is an identity column defined as GENERATED ALWAYS.
+HINT: Use OVERRIDING SYSTEM VALUE to override.
+MERGE INTO itest14 t
+USING (SELECT 30 AS s_a, 'inserted by merge' AS s_b) s
+ON t.a = s.s_a
+WHEN NOT MATCHED THEN
+ INSERT (a, b) OVERRIDING SYSTEM VALUE VALUES (s.s_a, s.s_b);
+MERGE INTO itest15 t
+USING (SELECT 10 AS s_a, 'inserted by merge' AS s_b) s
+ON t.a = s.s_a
+WHEN NOT MATCHED THEN
+ INSERT (a, b) VALUES (s.s_a, s.s_b);
+MERGE INTO itest15 t
+USING (SELECT 20 AS s_a, 'inserted by merge' AS s_b) s
+ON t.a = s.s_a
+WHEN NOT MATCHED THEN
+ INSERT (a, b) OVERRIDING USER VALUE VALUES (s.s_a, s.s_b);
+MERGE INTO itest15 t
+USING (SELECT 30 AS s_a, 'inserted by merge' AS s_b) s
+ON t.a = s.s_a
+WHEN NOT MATCHED THEN
+ INSERT (a, b) OVERRIDING SYSTEM VALUE VALUES (s.s_a, s.s_b);
+SELECT * FROM itest14;
+ a | b
+----+-------------------
+ 30 | inserted by merge
+(1 row)
+
+SELECT * FROM itest15;
+ a | b
+----+-------------------
+ 10 | inserted by merge
+ 1 | inserted by merge
+ 30 | inserted by merge
+(3 rows)
+
+DROP TABLE itest14;
+DROP TABLE itest15;
diff --git a/src/test/regress/expected/merge.out b/src/test/regress/expected/merge.out
new file mode 100644
index 0000000..67b3e81
--- /dev/null
+++ b/src/test/regress/expected/merge.out
@@ -0,0 +1,1503 @@
+--
+-- MERGE
+--
+--\set VERBOSITY verbose
+--set debug_print_rewritten = true;
+--set debug_print_parse = true;
+--set debug_print_pretty = true;
+CREATE USER merge_privs;
+CREATE USER merge_no_privs;
+DROP TABLE IF EXISTS target;
+NOTICE: table "target" does not exist, skipping
+DROP TABLE IF EXISTS source;
+NOTICE: table "source" does not exist, skipping
+CREATE TABLE target (tid integer, balance integer);
+CREATE TABLE source (sid integer, delta integer); --no index
+INSERT INTO target VALUES (1, 10);
+INSERT INTO target VALUES (2, 20);
+INSERT INTO target VALUES (3, 30);
+SELECT t.ctid is not null as matched, t.*, s.* FROM source s FULL OUTER JOIN target t ON s.sid = t.tid ORDER BY t.tid, s.sid;
+ matched | tid | balance | sid | delta
+---------+-----+---------+-----+-------
+ t | 1 | 10 | |
+ t | 2 | 20 | |
+ t | 3 | 30 | |
+(3 rows)
+
+ALTER TABLE target OWNER TO merge_privs;
+ALTER TABLE source OWNER TO merge_privs;
+CREATE TABLE target2 (tid integer, balance integer);
+CREATE TABLE source2 (sid integer, delta integer);
+ALTER TABLE target2 OWNER TO merge_no_privs;
+ALTER TABLE source2 OWNER TO merge_no_privs;
+GRANT INSERT ON target TO merge_no_privs;
+SET SESSION AUTHORIZATION merge_privs;
+EXPLAIN (COSTS OFF)
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ DELETE
+;
+ QUERY PLAN
+------------------------------------------
+ Merge on target t
+ -> Merge Join
+ Merge Cond: (t_1.tid = s.sid)
+ -> Sort
+ Sort Key: t_1.tid
+ -> Seq Scan on target t_1
+ -> Sort
+ Sort Key: s.sid
+ -> Seq Scan on source s
+(9 rows)
+
+--
+-- Errors
+--
+MERGE INTO target t RANDOMWORD
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+ERROR: syntax error at or near "RANDOMWORD"
+LINE 1: MERGE INTO target t RANDOMWORD
+ ^
+-- MATCHED/INSERT error
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ INSERT DEFAULT VALUES
+;
+ERROR: syntax error at or near "INSERT"
+LINE 5: INSERT DEFAULT VALUES
+ ^
+-- incorrectly specifying INTO target
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT INTO target DEFAULT VALUES
+;
+ERROR: syntax error at or near "INTO"
+LINE 5: INSERT INTO target DEFAULT VALUES
+ ^
+-- NOT MATCHED/UPDATE
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ UPDATE SET balance = 0
+;
+ERROR: syntax error at or near "UPDATE"
+LINE 5: UPDATE SET balance = 0
+ ^
+-- UPDATE tablename
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE target SET balance = 0
+;
+ERROR: syntax error at or near "target"
+LINE 5: UPDATE target SET balance = 0
+ ^
+-- permissions
+MERGE INTO target
+USING source2
+ON target.tid = source2.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+ERROR: permission denied for table source2
+GRANT INSERT ON target TO merge_no_privs;
+SET SESSION AUTHORIZATION merge_no_privs;
+MERGE INTO target
+USING source2
+ON target.tid = source2.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+ERROR: permission denied for table target
+GRANT UPDATE ON target2 TO merge_privs;
+SET SESSION AUTHORIZATION merge_privs;
+MERGE INTO target2
+USING source
+ON target2.tid = source.sid
+WHEN MATCHED THEN
+ DELETE
+;
+ERROR: permission denied for table target2
+MERGE INTO target2
+USING source
+ON target2.tid = source.sid
+WHEN NOT MATCHED THEN
+ INSERT DEFAULT VALUES
+;
+ERROR: permission denied for table target2
+--
+-- initial tests
+--
+-- zero rows in source has no effect
+MERGE INTO target
+USING source
+ON target.tid = source.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ DELETE
+;
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT DEFAULT VALUES
+;
+ROLLBACK;
+-- insert some non-matching source rows to work from
+INSERT INTO source VALUES (4, 40);
+SELECT * FROM source ORDER BY sid;
+ sid | delta
+-----+-------
+ 4 | 40
+(1 row)
+
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 20
+ 3 | 30
+(3 rows)
+
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ DO NOTHING
+;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ DELETE
+;
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT DEFAULT VALUES
+;
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 20
+ 3 | 30
+ |
+(4 rows)
+
+ROLLBACK;
+-- index plans
+INSERT INTO target SELECT generate_series(1000,2500), 0;
+ALTER TABLE target ADD PRIMARY KEY (tid);
+ANALYZE target;
+EXPLAIN (COSTS OFF)
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+ QUERY PLAN
+------------------------------------------
+ Merge on target t
+ -> Hash Join
+ Hash Cond: (s.sid = t_1.tid)
+ -> Seq Scan on source s
+ -> Hash
+ -> Seq Scan on target t_1
+(6 rows)
+
+EXPLAIN (COSTS OFF)
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ DELETE
+;
+ QUERY PLAN
+------------------------------------------
+ Merge on target t
+ -> Hash Join
+ Hash Cond: (s.sid = t_1.tid)
+ -> Seq Scan on source s
+ -> Hash
+ -> Seq Scan on target t_1
+(6 rows)
+
+EXPLAIN (COSTS OFF)
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT VALUES (4, NULL);
+ QUERY PLAN
+------------------------------------------
+ Merge on target t
+ -> Hash Left Join
+ Hash Cond: (s.sid = t_1.tid)
+ -> Seq Scan on source s
+ -> Hash
+ -> Seq Scan on target t_1
+(6 rows)
+
+;
+DELETE FROM target WHERE tid > 100;
+ANALYZE target;
+-- insert some matching source rows to work from
+INSERT INTO source VALUES (2, 5);
+INSERT INTO source VALUES (3, 20);
+SELECT * FROM source ORDER BY sid;
+ sid | delta
+-----+-------
+ 2 | 5
+ 3 | 20
+ 4 | 40
+(3 rows)
+
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 20
+ 3 | 30
+(3 rows)
+
+-- equivalent of an UPDATE join
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 0
+ 3 | 0
+(3 rows)
+
+ROLLBACK;
+-- equivalent of a DELETE join
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ DELETE
+;
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+(1 row)
+
+ROLLBACK;
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT VALUES (4, NULL)
+;
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 20
+ 3 | 30
+ 4 |
+(4 rows)
+
+ROLLBACK;
+-- duplicate source row causes multiple target row update ERROR
+INSERT INTO source VALUES (2, 5);
+SELECT * FROM source ORDER BY sid;
+ sid | delta
+-----+-------
+ 2 | 5
+ 2 | 5
+ 3 | 20
+ 4 | 40
+(4 rows)
+
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 20
+ 3 | 30
+(3 rows)
+
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+ERROR: MERGE command cannot affect row a second time
+ROLLBACK;
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ DELETE
+;
+ERROR: MERGE command cannot affect row a second time
+ROLLBACK;
+-- correct source data
+DELETE FROM source WHERE sid = 2;
+INSERT INTO source VALUES (2, 5);
+SELECT * FROM source ORDER BY sid;
+ sid | delta
+-----+-------
+ 2 | 5
+ 3 | 20
+ 4 | 40
+(3 rows)
+
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 20
+ 3 | 30
+(3 rows)
+
+-- remove constraints
+alter table target drop CONSTRAINT target_pkey;
+alter table target alter column tid drop not null;
+-- multiple actions
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT VALUES (4, 4)
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 0
+ 3 | 0
+ 4 | 4
+(4 rows)
+
+ROLLBACK;
+-- should be equivalent
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+WHEN NOT MATCHED THEN
+ INSERT VALUES (4, 4);
+;
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 0
+ 3 | 0
+ 4 | 4
+(4 rows)
+
+ROLLBACK;
+-- column references
+-- do a simple equivalent of an UPDATE join
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = t.balance + s.delta
+;
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 25
+ 3 | 50
+(3 rows)
+
+ROLLBACK;
+-- do a simple equivalent of an INSERT SELECT
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT VALUES (s.sid, s.delta)
+;
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 20
+ 3 | 30
+ 4 | 40
+(4 rows)
+
+ROLLBACK;
+-- and again with explicitly identified column list
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (s.sid, s.delta)
+;
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 20
+ 3 | 30
+ 4 | 40
+(4 rows)
+
+ROLLBACK;
+-- and again with a subtle error: referring to non-existent target row for NOT MATCHED
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (t.tid, s.delta)
+;
+ERROR: invalid reference to FROM-clause entry for table "t"
+LINE 5: INSERT (tid, balance) VALUES (t.tid, s.delta)
+ ^
+HINT: There is an entry for table "t", but it cannot be referenced from this part of the query.
+-- and again with a constant ON clause
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON (SELECT true)
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (t.tid, s.delta)
+;
+ERROR: invalid reference to FROM-clause entry for table "t"
+LINE 5: INSERT (tid, balance) VALUES (t.tid, s.delta)
+ ^
+HINT: There is an entry for table "t", but it cannot be referenced from this part of the query.
+SELECT * FROM target ORDER BY tid;
+ERROR: current transaction is aborted, commands ignored until end of transaction block
+ROLLBACK;
+-- now the classic UPSERT
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = t.balance + s.delta
+WHEN NOT MATCHED THEN
+ INSERT VALUES (s.sid, s.delta)
+;
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 25
+ 3 | 50
+ 4 | 40
+(4 rows)
+
+ROLLBACK;
+-- unreachable WHEN clause should ERROR
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN /* Terminal WHEN clause for MATCHED */
+ DELETE
+WHEN MATCHED AND s.delta > 0 THEN
+ UPDATE SET balance = t.balance - s.delta
+;
+ERROR: unreachable WHEN clause specified after unconditional WHEN clause
+ROLLBACK;
+-- conditional WHEN clause
+CREATE TABLE wq_target (tid integer not null, balance integer DEFAULT -1);
+CREATE TABLE wq_source (balance integer, sid integer);
+INSERT INTO wq_source (sid, balance) VALUES (1, 100);
+BEGIN;
+-- try a simple INSERT with default values first
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid) VALUES (s.sid);
+SELECT * FROM wq_target;
+ tid | balance
+-----+---------
+ 1 | -1
+(1 row)
+
+ROLLBACK;
+-- this time with a FALSE condition
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN NOT MATCHED AND FALSE THEN
+ INSERT (tid) VALUES (s.sid);
+SELECT * FROM wq_target;
+ tid | balance
+-----+---------
+(0 rows)
+
+-- this time with an actual condition which returns false
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN NOT MATCHED AND s.balance <> 100 THEN
+ INSERT (tid) VALUES (s.sid);
+SELECT * FROM wq_target;
+ tid | balance
+-----+---------
+(0 rows)
+
+BEGIN;
+-- and now with a condition which returns true
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN NOT MATCHED AND s.balance = 100 THEN
+ INSERT (tid) VALUES (s.sid);
+SELECT * FROM wq_target;
+ tid | balance
+-----+---------
+ 1 | -1
+(1 row)
+
+ROLLBACK;
+-- conditions in the NOT MATCHED clause can only refer to source columns
+BEGIN;
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN NOT MATCHED AND t.balance = 100 THEN
+ INSERT (tid) VALUES (s.sid);
+ERROR: invalid reference to FROM-clause entry for table "t"
+LINE 3: WHEN NOT MATCHED AND t.balance = 100 THEN
+ ^
+HINT: There is an entry for table "t", but it cannot be referenced from this part of the query.
+SELECT * FROM wq_target;
+ERROR: current transaction is aborted, commands ignored until end of transaction block
+ROLLBACK;
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN NOT MATCHED AND s.balance = 100 THEN
+ INSERT (tid) VALUES (s.sid);
+SELECT * FROM wq_target;
+ tid | balance
+-----+---------
+ 1 | -1
+(1 row)
+
+-- conditions in MATCHED clause can refer to both source and target
+SELECT * FROM wq_source;
+ balance | sid
+---------+-----
+ 100 | 1
+(1 row)
+
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND s.balance = 100 THEN
+ UPDATE SET balance = t.balance + s.balance;
+SELECT * FROM wq_target;
+ tid | balance
+-----+---------
+ 1 | 99
+(1 row)
+
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.balance = 100 THEN
+ UPDATE SET balance = t.balance + s.balance;
+SELECT * FROM wq_target;
+ tid | balance
+-----+---------
+ 1 | 99
+(1 row)
+
+-- check if AND works
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.balance = 99 AND s.balance > 100 THEN
+ UPDATE SET balance = t.balance + s.balance;
+SELECT * FROM wq_target;
+ tid | balance
+-----+---------
+ 1 | 99
+(1 row)
+
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.balance = 99 AND s.balance = 100 THEN
+ UPDATE SET balance = t.balance + s.balance;
+SELECT * FROM wq_target;
+ tid | balance
+-----+---------
+ 1 | 199
+(1 row)
+
+-- check if OR works
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.balance = 99 OR s.balance > 100 THEN
+ UPDATE SET balance = t.balance + s.balance;
+SELECT * FROM wq_target;
+ tid | balance
+-----+---------
+ 1 | 199
+(1 row)
+
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.balance = 199 OR s.balance > 100 THEN
+ UPDATE SET balance = t.balance + s.balance;
+SELECT * FROM wq_target;
+ tid | balance
+-----+---------
+ 1 | 299
+(1 row)
+
+-- check if subqueries work in the conditions?
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.balance > (SELECT max(balance) FROM target) THEN
+ UPDATE SET balance = t.balance + s.balance;
+-- check if we can access system columns in the conditions
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.xmin = t.xmax THEN
+ UPDATE SET balance = t.balance + s.balance;
+ERROR: system column "xmin" reference in WHEN AND condition is invalid
+LINE 3: WHEN MATCHED AND t.xmin = t.xmax THEN
+ ^
+ALTER TABLE wq_target SET WITH OIDS;
+SELECT * FROM wq_target;
+ tid | balance
+-----+---------
+ 1 | 399
+(1 row)
+
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.oid >= 0 THEN
+ UPDATE SET balance = t.balance + s.balance;
+SELECT * FROM wq_target;
+ tid | balance
+-----+---------
+ 1 | 499
+(1 row)
+
+-- test preventing WHEN AND conditions from writing to the database
+create or replace function merge_when_and_write() returns boolean
+language plpgsql as
+$$
+BEGIN
+ INSERT INTO target VALUES (100, 100);
+ RETURN TRUE;
+END;
+$$;
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND (merge_when_and_write()) THEN
+ UPDATE SET balance = t.balance + s.balance;
+ERROR: cannot write to database within WHEN AND condition
+drop function merge_when_and_write();
+DROP TABLE wq_target, wq_source;
+-- test triggers
+create or replace function merge_trigfunc () returns trigger
+language plpgsql as
+$$
+BEGIN
+ RAISE NOTICE '% % % trigger', TG_WHEN, TG_OP, TG_LEVEL;
+ IF (TG_WHEN = 'BEFORE' AND TG_LEVEL = 'ROW') THEN
+ IF (TG_OP = 'DELETE') THEN
+ RETURN OLD;
+ ELSE
+ RETURN NEW;
+ END IF;
+ ELSE
+ RETURN NULL;
+ END IF;
+END;
+$$;
+CREATE TRIGGER merge_bsi BEFORE INSERT ON target FOR EACH STATEMENT EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_bsu BEFORE UPDATE ON target FOR EACH STATEMENT EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_bsd BEFORE DELETE ON target FOR EACH STATEMENT EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_asi AFTER INSERT ON target FOR EACH STATEMENT EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_asu AFTER UPDATE ON target FOR EACH STATEMENT EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_asd AFTER DELETE ON target FOR EACH STATEMENT EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_bri BEFORE INSERT ON target FOR EACH ROW EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_bru BEFORE UPDATE ON target FOR EACH ROW EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_brd BEFORE DELETE ON target FOR EACH ROW EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_ari AFTER INSERT ON target FOR EACH ROW EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_aru AFTER UPDATE ON target FOR EACH ROW EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_ard AFTER DELETE ON target FOR EACH ROW EXECUTE PROCEDURE merge_trigfunc ();
+-- now the classic UPSERT, with a DELETE
+BEGIN;
+UPDATE target SET balance = 0 WHERE tid = 3;
+NOTICE: BEFORE UPDATE STATEMENT trigger
+NOTICE: BEFORE UPDATE ROW trigger
+NOTICE: AFTER UPDATE ROW trigger
+NOTICE: AFTER UPDATE STATEMENT trigger
+EXPLAIN (ANALYZE ON, COSTS OFF, SUMMARY OFF, TIMING OFF)
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED AND t.balance > s.delta THEN
+ UPDATE SET balance = t.balance - s.delta
+WHEN MATCHED THEN
+ DELETE
+WHEN NOT MATCHED THEN
+ INSERT VALUES (s.sid, s.delta)
+;
+NOTICE: BEFORE INSERT STATEMENT trigger
+NOTICE: BEFORE UPDATE STATEMENT trigger
+NOTICE: BEFORE DELETE STATEMENT trigger
+NOTICE: BEFORE INSERT ROW trigger
+NOTICE: BEFORE DELETE ROW trigger
+NOTICE: BEFORE UPDATE ROW trigger
+NOTICE: AFTER INSERT ROW trigger
+NOTICE: AFTER DELETE ROW trigger
+NOTICE: AFTER UPDATE ROW trigger
+NOTICE: AFTER DELETE STATEMENT trigger
+NOTICE: AFTER UPDATE STATEMENT trigger
+NOTICE: AFTER INSERT STATEMENT trigger
+ QUERY PLAN
+------------------------------------------------------------------
+ Merge on target t (actual rows=0 loops=1)
+ Tuples Inserted: 1
+ Tuples Updated: 1
+ Tuples Deleted: 1
+ -> Hash Left Join (actual rows=3 loops=1)
+ Hash Cond: (s.sid = t_1.tid)
+ -> Seq Scan on source s (actual rows=3 loops=1)
+ -> Hash (actual rows=3 loops=1)
+ Buckets: 1024 Batches: 1 Memory Usage: 9kB
+ -> Seq Scan on target t_1 (actual rows=3 loops=1)
+ Trigger merge_ard: calls=1
+ Trigger merge_ari: calls=1
+ Trigger merge_aru: calls=1
+ Trigger merge_asd: calls=1
+ Trigger merge_asi: calls=1
+ Trigger merge_asu: calls=1
+ Trigger merge_brd: calls=1
+ Trigger merge_bri: calls=1
+ Trigger merge_bru: calls=1
+ Trigger merge_bsd: calls=1
+ Trigger merge_bsi: calls=1
+ Trigger merge_bsu: calls=1
+(22 rows)
+
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 15
+ 4 | 40
+(3 rows)
+
+ROLLBACK;
+-- test from PL/pgSQL
+-- make sure MERGE INTO isn't interpreted to mean returning variables like SELECT INTO
+BEGIN;
+DO LANGUAGE plpgsql $$
+BEGIN
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED AND t.balance > s.delta THEN
+ UPDATE SET balance = t.balance - s.delta
+;
+END;
+$$;
+NOTICE: BEFORE UPDATE STATEMENT trigger
+NOTICE: BEFORE UPDATE ROW trigger
+NOTICE: BEFORE UPDATE ROW trigger
+NOTICE: AFTER UPDATE ROW trigger
+NOTICE: AFTER UPDATE ROW trigger
+NOTICE: AFTER UPDATE STATEMENT trigger
+ROLLBACK;
+--source constants
+BEGIN;
+MERGE INTO target t
+USING (SELECT 9 AS sid, 57 AS delta) AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (s.sid, s.delta)
+;
+NOTICE: BEFORE INSERT STATEMENT trigger
+NOTICE: BEFORE INSERT ROW trigger
+NOTICE: AFTER INSERT ROW trigger
+NOTICE: AFTER INSERT STATEMENT trigger
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 20
+ 3 | 30
+ 9 | 57
+(4 rows)
+
+ROLLBACK;
+--source query
+BEGIN;
+MERGE INTO target t
+USING (SELECT sid, delta FROM source WHERE delta > 0) AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (s.sid, s.delta)
+;
+NOTICE: BEFORE INSERT STATEMENT trigger
+NOTICE: BEFORE INSERT ROW trigger
+NOTICE: AFTER INSERT ROW trigger
+NOTICE: AFTER INSERT STATEMENT trigger
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 20
+ 3 | 30
+ 4 | 40
+(4 rows)
+
+ROLLBACK;
+BEGIN;
+MERGE INTO target t
+USING (SELECT sid, delta as newname FROM source WHERE delta > 0) AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (s.sid, s.newname)
+;
+NOTICE: BEFORE INSERT STATEMENT trigger
+NOTICE: BEFORE INSERT ROW trigger
+NOTICE: AFTER INSERT ROW trigger
+NOTICE: AFTER INSERT STATEMENT trigger
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 20
+ 3 | 30
+ 4 | 40
+(4 rows)
+
+ROLLBACK;
+--self-merge
+BEGIN;
+MERGE INTO target t1
+USING target t2
+ON t1.tid = t2.tid
+WHEN MATCHED THEN
+ UPDATE SET balance = t1.balance + t2.balance
+WHEN NOT MATCHED THEN
+ INSERT VALUES (t2.tid, t2.balance)
+;
+NOTICE: BEFORE INSERT STATEMENT trigger
+NOTICE: BEFORE UPDATE STATEMENT trigger
+NOTICE: BEFORE UPDATE ROW trigger
+NOTICE: BEFORE UPDATE ROW trigger
+NOTICE: BEFORE UPDATE ROW trigger
+NOTICE: AFTER UPDATE ROW trigger
+NOTICE: AFTER UPDATE ROW trigger
+NOTICE: AFTER UPDATE ROW trigger
+NOTICE: AFTER UPDATE STATEMENT trigger
+NOTICE: AFTER INSERT STATEMENT trigger
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 20
+ 2 | 40
+ 3 | 60
+(3 rows)
+
+ROLLBACK;
+BEGIN;
+MERGE INTO target t
+USING (SELECT tid as sid, balance as delta FROM target WHERE balance > 0) AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (s.sid, s.delta)
+;
+NOTICE: BEFORE INSERT STATEMENT trigger
+NOTICE: AFTER INSERT STATEMENT trigger
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 20
+ 3 | 30
+(3 rows)
+
+ROLLBACK;
+BEGIN;
+MERGE INTO target t
+USING
+(SELECT sid, max(delta) AS delta
+ FROM source
+ GROUP BY sid
+ HAVING count(*) = 1
+ ORDER BY sid ASC) AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (s.sid, s.delta)
+;
+NOTICE: BEFORE INSERT STATEMENT trigger
+NOTICE: BEFORE INSERT ROW trigger
+NOTICE: AFTER INSERT ROW trigger
+NOTICE: AFTER INSERT STATEMENT trigger
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 20
+ 3 | 30
+ 4 | 40
+(4 rows)
+
+ROLLBACK;
+-- plpgsql parameters and results
+BEGIN;
+CREATE FUNCTION merge_func (p_id integer, p_bal integer)
+RETURNS INTEGER
+LANGUAGE plpgsql
+AS $$
+DECLARE
+ result integer;
+BEGIN
+MERGE INTO target t
+USING (SELECT p_id AS sid) AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = t.balance - p_bal
+;
+IF FOUND THEN
+ GET DIAGNOSTICS result := ROW_COUNT;
+END IF;
+RETURN result;
+END;
+$$;
+SELECT merge_func(3, 4);
+NOTICE: BEFORE UPDATE STATEMENT trigger
+NOTICE: BEFORE UPDATE ROW trigger
+NOTICE: AFTER UPDATE ROW trigger
+NOTICE: AFTER UPDATE STATEMENT trigger
+ merge_func
+------------
+ 1
+(1 row)
+
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 10
+ 2 | 20
+ 3 | 26
+(3 rows)
+
+ROLLBACK;
+-- PREPARE
+BEGIN;
+prepare foom as merge into target t using (select 1 as sid) s on (t.tid = s.sid) when matched then update set balance = 1;
+execute foom;
+NOTICE: BEFORE UPDATE STATEMENT trigger
+NOTICE: BEFORE UPDATE ROW trigger
+NOTICE: AFTER UPDATE ROW trigger
+NOTICE: AFTER UPDATE STATEMENT trigger
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 1
+ 2 | 20
+ 3 | 30
+(3 rows)
+
+ROLLBACK;
+BEGIN;
+PREPARE foom2 (integer, integer) AS
+MERGE INTO target t
+USING (SELECT 1) s
+ON t.tid = $1
+WHEN MATCHED THEN
+UPDATE SET balance = $2;
+EXPLAIN (ANALYZE ON, COSTS OFF, SUMMARY OFF, TIMING OFF)
+execute foom2 (1, 1);
+NOTICE: BEFORE UPDATE STATEMENT trigger
+NOTICE: BEFORE UPDATE ROW trigger
+NOTICE: AFTER UPDATE ROW trigger
+NOTICE: AFTER UPDATE STATEMENT trigger
+ QUERY PLAN
+------------------------------------------------------
+ Merge on target t (actual rows=0 loops=1)
+ Tuples Inserted: 0
+ Tuples Updated: 1
+ Tuples Deleted: 0
+ -> Seq Scan on target t_1 (actual rows=1 loops=1)
+ Filter: (tid = 1)
+ Rows Removed by Filter: 2
+ Trigger merge_aru: calls=1
+ Trigger merge_asu: calls=1
+ Trigger merge_bru: calls=1
+ Trigger merge_bsu: calls=1
+(11 rows)
+
+SELECT * FROM target ORDER BY tid;
+ tid | balance
+-----+---------
+ 1 | 1
+ 2 | 20
+ 3 | 30
+(3 rows)
+
+ROLLBACK;
+-- subqueries in source relation
+CREATE TABLE sq_target (tid integer NOT NULL, balance integer);
+CREATE TABLE sq_source (delta integer, sid integer, balance integer DEFAULT 0);
+INSERT INTO sq_target(tid, balance) VALUES (1,100), (2,200), (3,300);
+INSERT INTO sq_source(sid, delta) VALUES (1,10), (2,20), (4,40);
+BEGIN;
+MERGE INTO sq_target t
+USING (SELECT * FROM sq_source) s
+ON tid = sid
+WHEN MATCHED AND t.balance > delta THEN
+ UPDATE SET balance = t.balance + delta;
+SELECT * FROM sq_target;
+ tid | balance
+-----+---------
+ 3 | 300
+ 1 | 110
+ 2 | 220
+(3 rows)
+
+ROLLBACK;
+-- try a view
+CREATE VIEW v AS SELECT * FROM sq_source WHERE sid < 2;
+BEGIN;
+MERGE INTO sq_target
+USING v
+ON tid = sid
+WHEN MATCHED THEN
+ UPDATE SET balance = v.balance + delta;
+SELECT * FROM sq_target;
+ tid | balance
+-----+---------
+ 2 | 200
+ 3 | 300
+ 1 | 10
+(3 rows)
+
+ROLLBACK;
+-- ambiguous reference to a column
+BEGIN;
+MERGE INTO sq_target
+USING v
+ON tid = sid
+WHEN MATCHED AND tid > 2 THEN
+ UPDATE SET balance = balance + delta
+WHEN NOT MATCHED THEN
+ INSERT (balance, tid) VALUES (balance + delta, sid)
+WHEN MATCHED AND tid < 2 THEN
+ DELETE;
+ERROR: column reference "balance" is ambiguous
+LINE 5: UPDATE SET balance = balance + delta
+ ^
+ROLLBACK;
+BEGIN;
+INSERT INTO sq_source (sid, balance, delta) VALUES (-1, -1, -10);
+MERGE INTO sq_target t
+USING v
+ON tid = sid
+WHEN MATCHED AND tid > 2 THEN
+ UPDATE SET balance = t.balance + delta
+WHEN NOT MATCHED THEN
+ INSERT (balance, tid) VALUES (balance + delta, sid)
+WHEN MATCHED AND tid < 2 THEN
+ DELETE;
+SELECT * FROM sq_target;
+ tid | balance
+-----+---------
+ 2 | 200
+ 3 | 300
+ -1 | -11
+(3 rows)
+
+ROLLBACK;
+-- CTEs
+BEGIN;
+INSERT INTO sq_source (sid, balance, delta) VALUES (-1, -1, -10);
+WITH targq AS (
+ SELECT * FROM v
+)
+MERGE INTO sq_target t
+USING v
+ON tid = sid
+WHEN MATCHED AND tid > 2 THEN
+ UPDATE SET balance = t.balance + delta
+WHEN NOT MATCHED THEN
+ INSERT (balance, tid) VALUES (balance + delta, sid)
+WHEN MATCHED AND tid < 2 THEN
+ DELETE
+;
+ERROR: syntax error at or near "MERGE"
+LINE 4: MERGE INTO sq_target t
+ ^
+ROLLBACK;
+-- RETURNING
+BEGIN;
+INSERT INTO sq_source (sid, balance, delta) VALUES (-1, -1, -10);
+MERGE INTO sq_target t
+USING v
+ON tid = sid
+WHEN MATCHED AND tid > 2 THEN
+ UPDATE SET balance = t.balance + delta
+WHEN NOT MATCHED THEN
+ INSERT (balance, tid) VALUES (balance + delta, sid)
+WHEN MATCHED AND tid < 2 THEN
+ DELETE
+RETURNING *
+;
+ERROR: syntax error at or near "RETURNING"
+LINE 10: RETURNING *
+ ^
+ROLLBACK;
+-- Subqueries
+BEGIN;
+MERGE INTO sq_target t
+USING v
+ON tid = sid
+WHEN MATCHED THEN
+ UPDATE SET balance = (SELECT count(*) FROM sq_target)
+;
+ROLLBACK;
+BEGIN;
+MERGE INTO sq_target t
+USING v
+ON tid = sid
+WHEN MATCHED AND (SELECT count(*) > 0 FROM sq_target) THEN
+ UPDATE SET balance = 42
+;
+ROLLBACK;
+BEGIN;
+MERGE INTO sq_target t
+USING v
+ON tid = sid AND (SELECT count(*) > 0 FROM sq_target)
+WHEN MATCHED THEN
+ UPDATE SET balance = 42
+;
+ROLLBACK;
+DROP TABLE sq_target, sq_source CASCADE;
+NOTICE: drop cascades to view v
+CREATE TABLE pa_target (tid integer, balance float, val text)
+ PARTITION BY LIST (tid);
+CREATE TABLE part1 PARTITION OF pa_target FOR VALUES IN (1,4);
+CREATE TABLE part2 PARTITION OF pa_target FOR VALUES IN (2,5,6);
+CREATE TABLE part3 PARTITION OF pa_target FOR VALUES IN (3,8,9);
+CREATE TABLE part4 PARTITION OF pa_target DEFAULT;
+CREATE TABLE pa_source (sid integer, delta float);
+-- insert many rows to the source table
+INSERT INTO pa_source SELECT id, id * 10 FROM generate_series(1,14) AS id;
+-- insert a few rows in the target table (odd numbered tid)
+INSERT INTO pa_target SELECT id, id * 100, 'initial' FROM generate_series(1,14,2) AS id;
+-- try simple MERGE
+BEGIN;
+MERGE INTO pa_target t
+ USING pa_source s
+ ON t.tid = s.sid
+ WHEN MATCHED THEN
+ UPDATE SET balance = balance + delta, val = val || ' updated by merge'
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (sid, delta, 'inserted by merge');
+SELECT * FROM pa_target ORDER BY tid;
+ tid | balance | val
+-----+---------+--------------------------
+ 1 | 110 | initial updated by merge
+ 2 | 20 | inserted by merge
+ 3 | 330 | initial updated by merge
+ 4 | 40 | inserted by merge
+ 5 | 550 | initial updated by merge
+ 6 | 60 | inserted by merge
+ 7 | 770 | initial updated by merge
+ 8 | 80 | inserted by merge
+ 9 | 990 | initial updated by merge
+ 10 | 100 | inserted by merge
+ 11 | 1210 | initial updated by merge
+ 12 | 120 | inserted by merge
+ 13 | 1430 | initial updated by merge
+ 14 | 140 | inserted by merge
+(14 rows)
+
+ROLLBACK;
+-- same with a constant qual
+BEGIN;
+MERGE INTO pa_target t
+ USING pa_source s
+ ON t.tid = s.sid AND tid = 1
+ WHEN MATCHED THEN
+ UPDATE SET balance = balance + delta, val = val || ' updated by merge'
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (sid, delta, 'inserted by merge');
+SELECT * FROM pa_target ORDER BY tid;
+ tid | balance | val
+-----+---------+--------------------------
+ 1 | 110 | initial updated by merge
+ 2 | 20 | inserted by merge
+ 3 | 30 | inserted by merge
+ 3 | 300 | initial
+ 4 | 40 | inserted by merge
+ 5 | 500 | initial
+ 5 | 50 | inserted by merge
+ 6 | 60 | inserted by merge
+ 7 | 700 | initial
+ 7 | 70 | inserted by merge
+ 8 | 80 | inserted by merge
+ 9 | 90 | inserted by merge
+ 9 | 900 | initial
+ 10 | 100 | inserted by merge
+ 11 | 1100 | initial
+ 11 | 110 | inserted by merge
+ 12 | 120 | inserted by merge
+ 13 | 1300 | initial
+ 13 | 130 | inserted by merge
+ 14 | 140 | inserted by merge
+(20 rows)
+
+ROLLBACK;
+-- try updating the partition key column
+BEGIN;
+MERGE INTO pa_target t
+ USING pa_source s
+ ON t.tid = s.sid
+ WHEN MATCHED THEN
+ UPDATE SET tid = tid + 1, balance = balance + delta, val = val || ' updated by merge'
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (sid, delta, 'inserted by merge');
+SELECT * FROM pa_target ORDER BY tid;
+ tid | balance | val
+-----+---------+--------------------------
+ 2 | 110 | initial updated by merge
+ 2 | 20 | inserted by merge
+ 4 | 40 | inserted by merge
+ 4 | 330 | initial updated by merge
+ 6 | 550 | initial updated by merge
+ 6 | 60 | inserted by merge
+ 8 | 80 | inserted by merge
+ 8 | 770 | initial updated by merge
+ 10 | 990 | initial updated by merge
+ 10 | 100 | inserted by merge
+ 12 | 1210 | initial updated by merge
+ 12 | 120 | inserted by merge
+ 14 | 1430 | initial updated by merge
+ 14 | 140 | inserted by merge
+(14 rows)
+
+ROLLBACK;
+DROP TABLE pa_target CASCADE;
+-- The target table is partitioned in the same way, but this time by attaching
+-- partitions which have columns in different order, dropped columns etc.
+CREATE TABLE pa_target (tid integer, balance float, val text)
+ PARTITION BY LIST (tid);
+CREATE TABLE part1 (tid integer, balance float, val text);
+CREATE TABLE part2 (balance float, tid integer, val text);
+CREATE TABLE part3 (tid integer, balance float, val text);
+CREATE TABLE part4 (extraid text, tid integer, balance float, val text);
+ALTER TABLE part4 DROP COLUMN extraid;
+ALTER TABLE pa_target ATTACH PARTITION part1 FOR VALUES IN (1,4);
+ALTER TABLE pa_target ATTACH PARTITION part2 FOR VALUES IN (2,5,6);
+ALTER TABLE pa_target ATTACH PARTITION part3 FOR VALUES IN (3,8,9);
+ALTER TABLE pa_target ATTACH PARTITION part4 DEFAULT;
+-- insert a few rows in the target table (odd numbered tid)
+INSERT INTO pa_target SELECT id, id * 100, 'initial' FROM generate_series(1,14,2) AS id;
+-- try simple MERGE
+BEGIN;
+MERGE INTO pa_target t
+ USING pa_source s
+ ON t.tid = s.sid
+ WHEN MATCHED THEN
+ UPDATE SET balance = balance + delta, val = val || ' updated by merge'
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (sid, delta, 'inserted by merge');
+SELECT * FROM pa_target ORDER BY tid;
+ tid | balance | val
+-----+---------+--------------------------
+ 1 | 110 | initial updated by merge
+ 2 | 20 | inserted by merge
+ 3 | 330 | initial updated by merge
+ 4 | 40 | inserted by merge
+ 5 | 550 | initial updated by merge
+ 6 | 60 | inserted by merge
+ 7 | 770 | initial updated by merge
+ 8 | 80 | inserted by merge
+ 9 | 990 | initial updated by merge
+ 10 | 100 | inserted by merge
+ 11 | 1210 | initial updated by merge
+ 12 | 120 | inserted by merge
+ 13 | 1430 | initial updated by merge
+ 14 | 140 | inserted by merge
+(14 rows)
+
+ROLLBACK;
+-- same with a constant qual
+BEGIN;
+MERGE INTO pa_target t
+ USING pa_source s
+ ON t.tid = s.sid AND tid = 1
+ WHEN MATCHED THEN
+ UPDATE SET balance = balance + delta, val = val || ' updated by merge'
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (sid, delta, 'inserted by merge');
+SELECT * FROM pa_target ORDER BY tid;
+ tid | balance | val
+-----+---------+--------------------------
+ 1 | 110 | initial updated by merge
+ 2 | 20 | inserted by merge
+ 3 | 30 | inserted by merge
+ 3 | 300 | initial
+ 4 | 40 | inserted by merge
+ 5 | 500 | initial
+ 5 | 50 | inserted by merge
+ 6 | 60 | inserted by merge
+ 7 | 700 | initial
+ 7 | 70 | inserted by merge
+ 8 | 80 | inserted by merge
+ 9 | 90 | inserted by merge
+ 9 | 900 | initial
+ 10 | 100 | inserted by merge
+ 11 | 1100 | initial
+ 11 | 110 | inserted by merge
+ 12 | 120 | inserted by merge
+ 13 | 1300 | initial
+ 13 | 130 | inserted by merge
+ 14 | 140 | inserted by merge
+(20 rows)
+
+ROLLBACK;
+-- try updating the partition key column
+BEGIN;
+MERGE INTO pa_target t
+ USING pa_source s
+ ON t.tid = s.sid
+ WHEN MATCHED THEN
+ UPDATE SET tid = tid + 1, balance = balance + delta, val = val || ' updated by merge'
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (sid, delta, 'inserted by merge');
+SELECT * FROM pa_target ORDER BY tid;
+ tid | balance | val
+-----+---------+--------------------------
+ 2 | 110 | initial updated by merge
+ 2 | 20 | inserted by merge
+ 4 | 40 | inserted by merge
+ 4 | 330 | initial updated by merge
+ 6 | 550 | initial updated by merge
+ 6 | 60 | inserted by merge
+ 8 | 80 | inserted by merge
+ 8 | 770 | initial updated by merge
+ 10 | 990 | initial updated by merge
+ 10 | 100 | inserted by merge
+ 12 | 1210 | initial updated by merge
+ 12 | 120 | inserted by merge
+ 14 | 1430 | initial updated by merge
+ 14 | 140 | inserted by merge
+(14 rows)
+
+ROLLBACK;
+DROP TABLE pa_source;
+DROP TABLE pa_target CASCADE;
+-- some complex joins on the source side
+CREATE TABLE cj_target (tid integer, balance float, val text);
+CREATE TABLE cj_source1 (sid1 integer, scat integer, delta integer);
+CREATE TABLE cj_source2 (sid2 integer, sval text);
+INSERT INTO cj_source1 VALUES (1, 10, 100);
+INSERT INTO cj_source1 VALUES (1, 20, 200);
+INSERT INTO cj_source1 VALUES (2, 20, 300);
+INSERT INTO cj_source1 VALUES (3, 10, 400);
+INSERT INTO cj_source2 VALUES (1, 'initial source2');
+INSERT INTO cj_source2 VALUES (2, 'initial source2');
+INSERT INTO cj_source2 VALUES (3, 'initial source2');
+-- source relation is an unalised join
+MERGE INTO cj_target t
+USING cj_source1 s1
+ INNER JOIN cj_source2 s2 ON sid1 = sid2
+ON t.tid = sid1
+WHEN NOT MATCHED THEN
+ INSERT VALUES (sid1, delta, sval);
+-- try accessing columns from either side of the source join
+MERGE INTO cj_target t
+USING cj_source2 s2
+ INNER JOIN cj_source1 s1 ON sid1 = sid2 AND scat = 20
+ON t.tid = sid1
+WHEN NOT MATCHED THEN
+ INSERT VALUES (sid2, delta, sval)
+WHEN MATCHED THEN
+ DELETE;
+-- some simple expressions in INSERT targetlist
+MERGE INTO cj_target t
+USING cj_source2 s2
+ INNER JOIN cj_source1 s1 ON sid1 = sid2
+ON t.tid = sid1
+WHEN NOT MATCHED THEN
+ INSERT VALUES (sid2, delta + scat, sval)
+WHEN MATCHED THEN
+ UPDATE SET val = val || ' updated by merge';
+MERGE INTO cj_target t
+USING cj_source2 s2
+ INNER JOIN cj_source1 s1 ON sid1 = sid2 AND scat = 20
+ON t.tid = sid1
+WHEN MATCHED THEN
+ UPDATE SET val = val || ' ' || delta::text;
+SELECT * FROM cj_target;
+ tid | balance | val
+-----+---------+----------------------------------
+ 3 | 400 | initial source2 updated by merge
+ 1 | 220 | initial source2 200
+ 1 | 110 | initial source2 200
+ 2 | 320 | initial source2 300
+(4 rows)
+
+DROP TABLE cj_source2, cj_source1, cj_target;
+-- SERIALIZABLE test
+-- handled in isolation tests
+-- prepare
+RESET SESSION AUTHORIZATION;
+DROP TABLE target, target2;
+DROP TABLE source, source2;
+DROP FUNCTION merge_trigfunc();
+DROP USER merge_privs;
+DROP USER merge_no_privs;
diff --git a/src/test/regress/expected/rowsecurity.out b/src/test/regress/expected/rowsecurity.out
index f1ae40d..b14a91e 100644
--- a/src/test/regress/expected/rowsecurity.out
+++ b/src/test/regress/expected/rowsecurity.out
@@ -2139,6 +2139,159 @@ INSERT INTO document VALUES (1, (SELECT cid from category WHERE cname = 'novel')
ON CONFLICT (did) DO UPDATE SET dauthor = 'regress_rls_carol';
ERROR: new row violates row-level security policy for table "document"
--
+-- MERGE
+--
+RESET SESSION AUTHORIZATION;
+DROP POLICY p3_with_all ON document;
+ALTER TABLE document ADD COLUMN dnotes text DEFAULT '';
+-- all documents are readable
+CREATE POLICY p1 ON document FOR SELECT USING (true);
+-- one may insert documents only authored by them
+CREATE POLICY p2 ON document FOR INSERT WITH CHECK (dauthor = current_user);
+-- one may only update documents in 'novel' category
+CREATE POLICY p3 ON document FOR UPDATE
+ USING (cid = (SELECT cid from category WHERE cname = 'novel'))
+ WITH CHECK (dauthor = current_user);
+-- one may only delete documents in 'manga' category
+CREATE POLICY p4 ON document FOR DELETE
+ USING (cid = (SELECT cid from category WHERE cname = 'manga'));
+SELECT * FROM document;
+ did | cid | dlevel | dauthor | dtitle | dnotes
+-----+-----+--------+-------------------+----------------------------------+--------
+ 1 | 11 | 1 | regress_rls_bob | my first novel |
+ 3 | 22 | 2 | regress_rls_bob | my science fiction |
+ 4 | 44 | 1 | regress_rls_bob | my first manga |
+ 5 | 44 | 2 | regress_rls_bob | my second manga |
+ 6 | 22 | 1 | regress_rls_carol | great science fiction |
+ 7 | 33 | 2 | regress_rls_carol | great technology book |
+ 8 | 44 | 1 | regress_rls_carol | great manga |
+ 9 | 22 | 1 | regress_rls_dave | awesome science fiction |
+ 10 | 33 | 2 | regress_rls_dave | awesome technology book |
+ 11 | 33 | 1 | regress_rls_carol | hoge |
+ 33 | 22 | 1 | regress_rls_bob | okay science fiction |
+ 2 | 11 | 2 | regress_rls_bob | my first novel |
+ 78 | 33 | 1 | regress_rls_bob | some technology novel |
+ 79 | 33 | 1 | regress_rls_bob | technology book, can only insert |
+(14 rows)
+
+SET SESSION AUTHORIZATION regress_rls_bob;
+-- Fails, since update violates WITH CHECK qual on dauthor
+MERGE INTO document d
+USING (SELECT 1 as sdid) s
+ON did = s.sdid
+WHEN MATCHED THEN
+ UPDATE SET dnotes = dnotes || ' notes added by merge1 ', dauthor = 'regress_rls_alice';
+ERROR: new row violates row-level security policy for table "document"
+-- Should be OK since USING and WITH CHECK quals pass
+MERGE INTO document d
+USING (SELECT 1 as sdid) s
+ON did = s.sdid
+WHEN MATCHED THEN
+ UPDATE SET dnotes = dnotes || ' notes added by merge2 ';
+-- Even when dauthor is updated explicitly, but to the existing value
+MERGE INTO document d
+USING (SELECT 1 as sdid) s
+ON did = s.sdid
+WHEN MATCHED THEN
+ UPDATE SET dnotes = dnotes || ' notes added by merge3 ', dauthor = 'regress_rls_bob';
+-- There is a MATCH for did = 3, but UPDATE's USING qual does not allow
+-- updating an item in category 'science fiction'
+MERGE INTO document d
+USING (SELECT 3 as sdid) s
+ON did = s.sdid
+WHEN MATCHED THEN
+ UPDATE SET dnotes = dnotes || ' notes added by merge ';
+ERROR: target row violates row-level security policy (USING expression) for table "document"
+-- The same thing with DELETE action, but fails again because no permissions
+-- to delete items in 'science fiction' category that did 3 belongs to.
+MERGE INTO document d
+USING (SELECT 3 as sdid) s
+ON did = s.sdid
+WHEN MATCHED THEN
+ DELETE;
+ERROR: target row violates row-level security policy (USING expression) for table "document"
+-- Document with did 4 belongs to 'manga' category which is allowed for
+-- deletion. But this fails because the UPDATE action is matched first and
+-- UPDATE policy does not allow updation in the category.
+MERGE INTO document d
+USING (SELECT 4 as sdid) s
+ON did = s.sdid
+WHEN MATCHED AND dnotes = '' THEN
+ UPDATE SET dnotes = dnotes || ' notes added by merge '
+WHEN MATCHED THEN
+ DELETE;
+ERROR: target row violates row-level security policy (USING expression) for table "document"
+-- UPDATE action is not matched this time because of the WHEN AND qual.
+-- DELETE still fails because role regress_rls_bob does not have SELECT
+-- privileges on 'manga' category row in the category table.
+MERGE INTO document d
+USING (SELECT 4 as sdid) s
+ON did = s.sdid
+WHEN MATCHED AND dnotes <> '' THEN
+ UPDATE SET dnotes = dnotes || ' notes added by merge '
+WHEN MATCHED THEN
+ DELETE;
+ERROR: target row violates row-level security policy (USING expression) for table "document"
+SELECT * FROM document WHERE did = 4;
+ did | cid | dlevel | dauthor | dtitle | dnotes
+-----+-----+--------+-----------------+----------------+--------
+ 4 | 44 | 1 | regress_rls_bob | my first manga |
+(1 row)
+
+-- Switch to regress_rls_carol role and try the DELETE again. It should succeed
+-- this time
+RESET SESSION AUTHORIZATION;
+SET SESSION AUTHORIZATION regress_rls_carol;
+MERGE INTO document d
+USING (SELECT 4 as sdid) s
+ON did = s.sdid
+WHEN MATCHED AND dnotes <> '' THEN
+ UPDATE SET dnotes = dnotes || ' notes added by merge '
+WHEN MATCHED THEN
+ DELETE;
+-- Switch back to regress_rls_bob role
+RESET SESSION AUTHORIZATION;
+SET SESSION AUTHORIZATION regress_rls_bob;
+-- Try INSERT action. This fails because we are trying to insert
+-- dauthor = regress_rls_dave and INSERT's WITH CHECK does not allow
+-- that
+MERGE INTO document d
+USING (SELECT 12 as sdid) s
+ON did = s.sdid
+WHEN MATCHED THEN
+ DELETE
+WHEN NOT MATCHED THEN
+ INSERT VALUES (12, 11, 1, 'regress_rls_dave', 'another novel');
+ERROR: new row violates row-level security policy for table "document"
+-- This should be fine
+MERGE INTO document d
+USING (SELECT 12 as sdid) s
+ON did = s.sdid
+WHEN MATCHED THEN
+ DELETE
+WHEN NOT MATCHED THEN
+ INSERT VALUES (12, 11, 1, 'regress_rls_bob', 'another novel');
+-- Just check everything went per plan
+SELECT * FROM document;
+ did | cid | dlevel | dauthor | dtitle | dnotes
+-----+-----+--------+-------------------+----------------------------------+------------------------------------------------
+ 3 | 22 | 2 | regress_rls_bob | my science fiction |
+ 5 | 44 | 2 | regress_rls_bob | my second manga |
+ 6 | 22 | 1 | regress_rls_carol | great science fiction |
+ 7 | 33 | 2 | regress_rls_carol | great technology book |
+ 8 | 44 | 1 | regress_rls_carol | great manga |
+ 9 | 22 | 1 | regress_rls_dave | awesome science fiction |
+ 10 | 33 | 2 | regress_rls_dave | awesome technology book |
+ 11 | 33 | 1 | regress_rls_carol | hoge |
+ 33 | 22 | 1 | regress_rls_bob | okay science fiction |
+ 2 | 11 | 2 | regress_rls_bob | my first novel |
+ 78 | 33 | 1 | regress_rls_bob | some technology novel |
+ 79 | 33 | 1 | regress_rls_bob | technology book, can only insert |
+ 1 | 11 | 1 | regress_rls_bob | my first novel | notes added by merge2 notes added by merge3
+ 12 | 11 | 1 | regress_rls_bob | another novel |
+(14 rows)
+
+--
-- ROLE/GROUP
--
SET SESSION AUTHORIZATION regress_rls_alice;
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
index ad9434f..63807b3 100644
--- a/src/test/regress/parallel_schedule
+++ b/src/test/regress/parallel_schedule
@@ -84,7 +84,7 @@ test: select_into select_distinct select_distinct_on select_implicit select_havi
# ----------
# Another group of parallel tests
# ----------
-test: brin gin gist spgist privileges init_privs security_label collate matview lock replica_identity rowsecurity object_address tablesample groupingsets drop_operator password
+test: brin gin gist spgist privileges init_privs security_label collate matview lock replica_identity rowsecurity object_address tablesample groupingsets drop_operator password merge
# ----------
# Another group of parallel tests
diff --git a/src/test/regress/serial_schedule b/src/test/regress/serial_schedule
index 27cd498..d2cb567 100644
--- a/src/test/regress/serial_schedule
+++ b/src/test/regress/serial_schedule
@@ -122,6 +122,7 @@ test: tablesample
test: groupingsets
test: drop_operator
test: password
+test: merge
test: alter_generic
test: alter_operator
test: misc
diff --git a/src/test/regress/sql/identity.sql b/src/test/regress/sql/identity.sql
index 8be086d..29a45ec 100644
--- a/src/test/regress/sql/identity.sql
+++ b/src/test/regress/sql/identity.sql
@@ -246,3 +246,48 @@ CREATE TABLE itest_child PARTITION OF itest_parent (
f3 WITH OPTIONS GENERATED ALWAYS AS IDENTITY
) FOR VALUES FROM ('2016-07-01') TO ('2016-08-01'); -- error
DROP TABLE itest_parent;
+
+-- MERGE tests
+CREATE TABLE itest14 (a int GENERATED ALWAYS AS IDENTITY, b text);
+CREATE TABLE itest15 (a int GENERATED BY DEFAULT AS IDENTITY, b text);
+
+MERGE INTO itest14 t
+USING (SELECT 10 AS s_a, 'inserted by merge' AS s_b) s
+ON t.a = s.s_a
+WHEN NOT MATCHED THEN
+ INSERT (a, b) VALUES (s.s_a, s.s_b);
+
+MERGE INTO itest14 t
+USING (SELECT 20 AS s_a, 'inserted by merge' AS s_b) s
+ON t.a = s.s_a
+WHEN NOT MATCHED THEN
+ INSERT (a, b) OVERRIDING USER VALUE VALUES (s.s_a, s.s_b);
+
+MERGE INTO itest14 t
+USING (SELECT 30 AS s_a, 'inserted by merge' AS s_b) s
+ON t.a = s.s_a
+WHEN NOT MATCHED THEN
+ INSERT (a, b) OVERRIDING SYSTEM VALUE VALUES (s.s_a, s.s_b);
+
+MERGE INTO itest15 t
+USING (SELECT 10 AS s_a, 'inserted by merge' AS s_b) s
+ON t.a = s.s_a
+WHEN NOT MATCHED THEN
+ INSERT (a, b) VALUES (s.s_a, s.s_b);
+
+MERGE INTO itest15 t
+USING (SELECT 20 AS s_a, 'inserted by merge' AS s_b) s
+ON t.a = s.s_a
+WHEN NOT MATCHED THEN
+ INSERT (a, b) OVERRIDING USER VALUE VALUES (s.s_a, s.s_b);
+
+MERGE INTO itest15 t
+USING (SELECT 30 AS s_a, 'inserted by merge' AS s_b) s
+ON t.a = s.s_a
+WHEN NOT MATCHED THEN
+ INSERT (a, b) OVERRIDING SYSTEM VALUE VALUES (s.s_a, s.s_b);
+
+SELECT * FROM itest14;
+SELECT * FROM itest15;
+DROP TABLE itest14;
+DROP TABLE itest15;
diff --git a/src/test/regress/sql/merge.sql b/src/test/regress/sql/merge.sql
new file mode 100644
index 0000000..bdcc19e
--- /dev/null
+++ b/src/test/regress/sql/merge.sql
@@ -0,0 +1,981 @@
+--
+-- MERGE
+--
+--\set VERBOSITY verbose
+
+--set debug_print_rewritten = true;
+--set debug_print_parse = true;
+--set debug_print_pretty = true;
+
+
+CREATE USER merge_privs;
+CREATE USER merge_no_privs;
+DROP TABLE IF EXISTS target;
+DROP TABLE IF EXISTS source;
+CREATE TABLE target (tid integer, balance integer);
+CREATE TABLE source (sid integer, delta integer); --no index
+INSERT INTO target VALUES (1, 10);
+INSERT INTO target VALUES (2, 20);
+INSERT INTO target VALUES (3, 30);
+SELECT t.ctid is not null as matched, t.*, s.* FROM source s FULL OUTER JOIN target t ON s.sid = t.tid ORDER BY t.tid, s.sid;
+
+ALTER TABLE target OWNER TO merge_privs;
+ALTER TABLE source OWNER TO merge_privs;
+
+CREATE TABLE target2 (tid integer, balance integer);
+CREATE TABLE source2 (sid integer, delta integer);
+
+ALTER TABLE target2 OWNER TO merge_no_privs;
+ALTER TABLE source2 OWNER TO merge_no_privs;
+
+GRANT INSERT ON target TO merge_no_privs;
+
+SET SESSION AUTHORIZATION merge_privs;
+
+EXPLAIN (COSTS OFF)
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ DELETE
+;
+
+--
+-- Errors
+--
+MERGE INTO target t RANDOMWORD
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+-- MATCHED/INSERT error
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ INSERT DEFAULT VALUES
+;
+-- incorrectly specifying INTO target
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT INTO target DEFAULT VALUES
+;
+-- NOT MATCHED/UPDATE
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ UPDATE SET balance = 0
+;
+-- UPDATE tablename
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE target SET balance = 0
+;
+
+-- permissions
+
+MERGE INTO target
+USING source2
+ON target.tid = source2.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+
+GRANT INSERT ON target TO merge_no_privs;
+SET SESSION AUTHORIZATION merge_no_privs;
+
+MERGE INTO target
+USING source2
+ON target.tid = source2.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+
+GRANT UPDATE ON target2 TO merge_privs;
+SET SESSION AUTHORIZATION merge_privs;
+
+MERGE INTO target2
+USING source
+ON target2.tid = source.sid
+WHEN MATCHED THEN
+ DELETE
+;
+
+MERGE INTO target2
+USING source
+ON target2.tid = source.sid
+WHEN NOT MATCHED THEN
+ INSERT DEFAULT VALUES
+;
+
+--
+-- initial tests
+--
+-- zero rows in source has no effect
+MERGE INTO target
+USING source
+ON target.tid = source.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ DELETE
+;
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT DEFAULT VALUES
+;
+ROLLBACK;
+
+-- insert some non-matching source rows to work from
+INSERT INTO source VALUES (4, 40);
+SELECT * FROM source ORDER BY sid;
+SELECT * FROM target ORDER BY tid;
+
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ DO NOTHING
+;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ DELETE
+;
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT DEFAULT VALUES
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+-- index plans
+INSERT INTO target SELECT generate_series(1000,2500), 0;
+ALTER TABLE target ADD PRIMARY KEY (tid);
+ANALYZE target;
+
+EXPLAIN (COSTS OFF)
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+EXPLAIN (COSTS OFF)
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ DELETE
+;
+EXPLAIN (COSTS OFF)
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT VALUES (4, NULL);
+;
+DELETE FROM target WHERE tid > 100;
+ANALYZE target;
+
+-- insert some matching source rows to work from
+INSERT INTO source VALUES (2, 5);
+INSERT INTO source VALUES (3, 20);
+SELECT * FROM source ORDER BY sid;
+SELECT * FROM target ORDER BY tid;
+
+-- equivalent of an UPDATE join
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+-- equivalent of a DELETE join
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ DELETE
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT VALUES (4, NULL)
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+-- duplicate source row causes multiple target row update ERROR
+INSERT INTO source VALUES (2, 5);
+SELECT * FROM source ORDER BY sid;
+SELECT * FROM target ORDER BY tid;
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+ROLLBACK;
+
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ DELETE
+;
+ROLLBACK;
+
+-- correct source data
+DELETE FROM source WHERE sid = 2;
+INSERT INTO source VALUES (2, 5);
+SELECT * FROM source ORDER BY sid;
+SELECT * FROM target ORDER BY tid;
+
+-- remove constraints
+alter table target drop CONSTRAINT target_pkey;
+alter table target alter column tid drop not null;
+
+-- multiple actions
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT VALUES (4, 4)
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+-- should be equivalent
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = 0
+WHEN NOT MATCHED THEN
+ INSERT VALUES (4, 4);
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+-- column references
+-- do a simple equivalent of an UPDATE join
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = t.balance + s.delta
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+-- do a simple equivalent of an INSERT SELECT
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT VALUES (s.sid, s.delta)
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+-- and again with explicitly identified column list
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (s.sid, s.delta)
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+-- and again with a subtle error: referring to non-existent target row for NOT MATCHED
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (t.tid, s.delta)
+;
+
+-- and again with a constant ON clause
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON (SELECT true)
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (t.tid, s.delta)
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+-- now the classic UPSERT
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = t.balance + s.delta
+WHEN NOT MATCHED THEN
+ INSERT VALUES (s.sid, s.delta)
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+-- unreachable WHEN clause should ERROR
+BEGIN;
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN /* Terminal WHEN clause for MATCHED */
+ DELETE
+WHEN MATCHED AND s.delta > 0 THEN
+ UPDATE SET balance = t.balance - s.delta
+;
+ROLLBACK;
+
+-- conditional WHEN clause
+CREATE TABLE wq_target (tid integer not null, balance integer DEFAULT -1);
+CREATE TABLE wq_source (balance integer, sid integer);
+
+INSERT INTO wq_source (sid, balance) VALUES (1, 100);
+
+BEGIN;
+-- try a simple INSERT with default values first
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid) VALUES (s.sid);
+SELECT * FROM wq_target;
+ROLLBACK;
+
+-- this time with a FALSE condition
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN NOT MATCHED AND FALSE THEN
+ INSERT (tid) VALUES (s.sid);
+SELECT * FROM wq_target;
+
+-- this time with an actual condition which returns false
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN NOT MATCHED AND s.balance <> 100 THEN
+ INSERT (tid) VALUES (s.sid);
+SELECT * FROM wq_target;
+
+BEGIN;
+-- and now with a condition which returns true
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN NOT MATCHED AND s.balance = 100 THEN
+ INSERT (tid) VALUES (s.sid);
+SELECT * FROM wq_target;
+ROLLBACK;
+
+-- conditions in the NOT MATCHED clause can only refer to source columns
+BEGIN;
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN NOT MATCHED AND t.balance = 100 THEN
+ INSERT (tid) VALUES (s.sid);
+SELECT * FROM wq_target;
+ROLLBACK;
+
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN NOT MATCHED AND s.balance = 100 THEN
+ INSERT (tid) VALUES (s.sid);
+SELECT * FROM wq_target;
+
+-- conditions in MATCHED clause can refer to both source and target
+SELECT * FROM wq_source;
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND s.balance = 100 THEN
+ UPDATE SET balance = t.balance + s.balance;
+SELECT * FROM wq_target;
+
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.balance = 100 THEN
+ UPDATE SET balance = t.balance + s.balance;
+SELECT * FROM wq_target;
+
+-- check if AND works
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.balance = 99 AND s.balance > 100 THEN
+ UPDATE SET balance = t.balance + s.balance;
+SELECT * FROM wq_target;
+
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.balance = 99 AND s.balance = 100 THEN
+ UPDATE SET balance = t.balance + s.balance;
+SELECT * FROM wq_target;
+
+-- check if OR works
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.balance = 99 OR s.balance > 100 THEN
+ UPDATE SET balance = t.balance + s.balance;
+SELECT * FROM wq_target;
+
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.balance = 199 OR s.balance > 100 THEN
+ UPDATE SET balance = t.balance + s.balance;
+SELECT * FROM wq_target;
+
+-- check if subqueries work in the conditions?
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.balance > (SELECT max(balance) FROM target) THEN
+ UPDATE SET balance = t.balance + s.balance;
+
+-- check if we can access system columns in the conditions
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.xmin = t.xmax THEN
+ UPDATE SET balance = t.balance + s.balance;
+
+ALTER TABLE wq_target SET WITH OIDS;
+SELECT * FROM wq_target;
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND t.oid >= 0 THEN
+ UPDATE SET balance = t.balance + s.balance;
+SELECT * FROM wq_target;
+
+-- test preventing WHEN AND conditions from writing to the database
+create or replace function merge_when_and_write() returns boolean
+language plpgsql as
+$$
+BEGIN
+ INSERT INTO target VALUES (100, 100);
+ RETURN TRUE;
+END;
+$$;
+MERGE INTO wq_target t
+USING wq_source s ON t.tid = s.sid
+WHEN MATCHED AND (merge_when_and_write()) THEN
+ UPDATE SET balance = t.balance + s.balance;
+drop function merge_when_and_write();
+
+DROP TABLE wq_target, wq_source;
+
+-- test triggers
+create or replace function merge_trigfunc () returns trigger
+language plpgsql as
+$$
+BEGIN
+ RAISE NOTICE '% % % trigger', TG_WHEN, TG_OP, TG_LEVEL;
+ IF (TG_WHEN = 'BEFORE' AND TG_LEVEL = 'ROW') THEN
+ IF (TG_OP = 'DELETE') THEN
+ RETURN OLD;
+ ELSE
+ RETURN NEW;
+ END IF;
+ ELSE
+ RETURN NULL;
+ END IF;
+END;
+$$;
+CREATE TRIGGER merge_bsi BEFORE INSERT ON target FOR EACH STATEMENT EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_bsu BEFORE UPDATE ON target FOR EACH STATEMENT EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_bsd BEFORE DELETE ON target FOR EACH STATEMENT EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_asi AFTER INSERT ON target FOR EACH STATEMENT EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_asu AFTER UPDATE ON target FOR EACH STATEMENT EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_asd AFTER DELETE ON target FOR EACH STATEMENT EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_bri BEFORE INSERT ON target FOR EACH ROW EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_bru BEFORE UPDATE ON target FOR EACH ROW EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_brd BEFORE DELETE ON target FOR EACH ROW EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_ari AFTER INSERT ON target FOR EACH ROW EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_aru AFTER UPDATE ON target FOR EACH ROW EXECUTE PROCEDURE merge_trigfunc ();
+CREATE TRIGGER merge_ard AFTER DELETE ON target FOR EACH ROW EXECUTE PROCEDURE merge_trigfunc ();
+
+-- now the classic UPSERT, with a DELETE
+BEGIN;
+UPDATE target SET balance = 0 WHERE tid = 3;
+EXPLAIN (ANALYZE ON, COSTS OFF, SUMMARY OFF, TIMING OFF)
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED AND t.balance > s.delta THEN
+ UPDATE SET balance = t.balance - s.delta
+WHEN MATCHED THEN
+ DELETE
+WHEN NOT MATCHED THEN
+ INSERT VALUES (s.sid, s.delta)
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+-- test from PL/pgSQL
+-- make sure MERGE INTO isn't interpreted to mean returning variables like SELECT INTO
+BEGIN;
+DO LANGUAGE plpgsql $$
+BEGIN
+MERGE INTO target t
+USING source AS s
+ON t.tid = s.sid
+WHEN MATCHED AND t.balance > s.delta THEN
+ UPDATE SET balance = t.balance - s.delta
+;
+END;
+$$;
+ROLLBACK;
+
+--source constants
+BEGIN;
+MERGE INTO target t
+USING (SELECT 9 AS sid, 57 AS delta) AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (s.sid, s.delta)
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+--source query
+BEGIN;
+MERGE INTO target t
+USING (SELECT sid, delta FROM source WHERE delta > 0) AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (s.sid, s.delta)
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+BEGIN;
+MERGE INTO target t
+USING (SELECT sid, delta as newname FROM source WHERE delta > 0) AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (s.sid, s.newname)
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+--self-merge
+BEGIN;
+MERGE INTO target t1
+USING target t2
+ON t1.tid = t2.tid
+WHEN MATCHED THEN
+ UPDATE SET balance = t1.balance + t2.balance
+WHEN NOT MATCHED THEN
+ INSERT VALUES (t2.tid, t2.balance)
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+BEGIN;
+MERGE INTO target t
+USING (SELECT tid as sid, balance as delta FROM target WHERE balance > 0) AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (s.sid, s.delta)
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+BEGIN;
+MERGE INTO target t
+USING
+(SELECT sid, max(delta) AS delta
+ FROM source
+ GROUP BY sid
+ HAVING count(*) = 1
+ ORDER BY sid ASC) AS s
+ON t.tid = s.sid
+WHEN NOT MATCHED THEN
+ INSERT (tid, balance) VALUES (s.sid, s.delta)
+;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+-- plpgsql parameters and results
+BEGIN;
+CREATE FUNCTION merge_func (p_id integer, p_bal integer)
+RETURNS INTEGER
+LANGUAGE plpgsql
+AS $$
+DECLARE
+ result integer;
+BEGIN
+MERGE INTO target t
+USING (SELECT p_id AS sid) AS s
+ON t.tid = s.sid
+WHEN MATCHED THEN
+ UPDATE SET balance = t.balance - p_bal
+;
+IF FOUND THEN
+ GET DIAGNOSTICS result := ROW_COUNT;
+END IF;
+RETURN result;
+END;
+$$;
+SELECT merge_func(3, 4);
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+-- PREPARE
+BEGIN;
+prepare foom as merge into target t using (select 1 as sid) s on (t.tid = s.sid) when matched then update set balance = 1;
+execute foom;
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+BEGIN;
+PREPARE foom2 (integer, integer) AS
+MERGE INTO target t
+USING (SELECT 1) s
+ON t.tid = $1
+WHEN MATCHED THEN
+UPDATE SET balance = $2;
+EXPLAIN (ANALYZE ON, COSTS OFF, SUMMARY OFF, TIMING OFF)
+execute foom2 (1, 1);
+SELECT * FROM target ORDER BY tid;
+ROLLBACK;
+
+-- subqueries in source relation
+
+CREATE TABLE sq_target (tid integer NOT NULL, balance integer);
+CREATE TABLE sq_source (delta integer, sid integer, balance integer DEFAULT 0);
+
+INSERT INTO sq_target(tid, balance) VALUES (1,100), (2,200), (3,300);
+INSERT INTO sq_source(sid, delta) VALUES (1,10), (2,20), (4,40);
+
+BEGIN;
+MERGE INTO sq_target t
+USING (SELECT * FROM sq_source) s
+ON tid = sid
+WHEN MATCHED AND t.balance > delta THEN
+ UPDATE SET balance = t.balance + delta;
+SELECT * FROM sq_target;
+ROLLBACK;
+
+-- try a view
+CREATE VIEW v AS SELECT * FROM sq_source WHERE sid < 2;
+
+BEGIN;
+MERGE INTO sq_target
+USING v
+ON tid = sid
+WHEN MATCHED THEN
+ UPDATE SET balance = v.balance + delta;
+SELECT * FROM sq_target;
+ROLLBACK;
+
+-- ambiguous reference to a column
+BEGIN;
+MERGE INTO sq_target
+USING v
+ON tid = sid
+WHEN MATCHED AND tid > 2 THEN
+ UPDATE SET balance = balance + delta
+WHEN NOT MATCHED THEN
+ INSERT (balance, tid) VALUES (balance + delta, sid)
+WHEN MATCHED AND tid < 2 THEN
+ DELETE;
+ROLLBACK;
+
+BEGIN;
+INSERT INTO sq_source (sid, balance, delta) VALUES (-1, -1, -10);
+MERGE INTO sq_target t
+USING v
+ON tid = sid
+WHEN MATCHED AND tid > 2 THEN
+ UPDATE SET balance = t.balance + delta
+WHEN NOT MATCHED THEN
+ INSERT (balance, tid) VALUES (balance + delta, sid)
+WHEN MATCHED AND tid < 2 THEN
+ DELETE;
+SELECT * FROM sq_target;
+ROLLBACK;
+
+-- CTEs
+BEGIN;
+INSERT INTO sq_source (sid, balance, delta) VALUES (-1, -1, -10);
+WITH targq AS (
+ SELECT * FROM v
+)
+MERGE INTO sq_target t
+USING v
+ON tid = sid
+WHEN MATCHED AND tid > 2 THEN
+ UPDATE SET balance = t.balance + delta
+WHEN NOT MATCHED THEN
+ INSERT (balance, tid) VALUES (balance + delta, sid)
+WHEN MATCHED AND tid < 2 THEN
+ DELETE
+;
+ROLLBACK;
+
+-- RETURNING
+BEGIN;
+INSERT INTO sq_source (sid, balance, delta) VALUES (-1, -1, -10);
+MERGE INTO sq_target t
+USING v
+ON tid = sid
+WHEN MATCHED AND tid > 2 THEN
+ UPDATE SET balance = t.balance + delta
+WHEN NOT MATCHED THEN
+ INSERT (balance, tid) VALUES (balance + delta, sid)
+WHEN MATCHED AND tid < 2 THEN
+ DELETE
+RETURNING *
+;
+ROLLBACK;
+
+-- Subqueries
+BEGIN;
+MERGE INTO sq_target t
+USING v
+ON tid = sid
+WHEN MATCHED THEN
+ UPDATE SET balance = (SELECT count(*) FROM sq_target)
+;
+ROLLBACK;
+
+BEGIN;
+MERGE INTO sq_target t
+USING v
+ON tid = sid
+WHEN MATCHED AND (SELECT count(*) > 0 FROM sq_target) THEN
+ UPDATE SET balance = 42
+;
+ROLLBACK;
+
+BEGIN;
+MERGE INTO sq_target t
+USING v
+ON tid = sid AND (SELECT count(*) > 0 FROM sq_target)
+WHEN MATCHED THEN
+ UPDATE SET balance = 42
+;
+ROLLBACK;
+
+DROP TABLE sq_target, sq_source CASCADE;
+
+CREATE TABLE pa_target (tid integer, balance float, val text)
+ PARTITION BY LIST (tid);
+
+CREATE TABLE part1 PARTITION OF pa_target FOR VALUES IN (1,4);
+CREATE TABLE part2 PARTITION OF pa_target FOR VALUES IN (2,5,6);
+CREATE TABLE part3 PARTITION OF pa_target FOR VALUES IN (3,8,9);
+CREATE TABLE part4 PARTITION OF pa_target DEFAULT;
+
+CREATE TABLE pa_source (sid integer, delta float);
+-- insert many rows to the source table
+INSERT INTO pa_source SELECT id, id * 10 FROM generate_series(1,14) AS id;
+-- insert a few rows in the target table (odd numbered tid)
+INSERT INTO pa_target SELECT id, id * 100, 'initial' FROM generate_series(1,14,2) AS id;
+
+-- try simple MERGE
+BEGIN;
+MERGE INTO pa_target t
+ USING pa_source s
+ ON t.tid = s.sid
+ WHEN MATCHED THEN
+ UPDATE SET balance = balance + delta, val = val || ' updated by merge'
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (sid, delta, 'inserted by merge');
+SELECT * FROM pa_target ORDER BY tid;
+ROLLBACK;
+
+-- same with a constant qual
+BEGIN;
+MERGE INTO pa_target t
+ USING pa_source s
+ ON t.tid = s.sid AND tid = 1
+ WHEN MATCHED THEN
+ UPDATE SET balance = balance + delta, val = val || ' updated by merge'
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (sid, delta, 'inserted by merge');
+SELECT * FROM pa_target ORDER BY tid;
+ROLLBACK;
+
+-- try updating the partition key column
+BEGIN;
+MERGE INTO pa_target t
+ USING pa_source s
+ ON t.tid = s.sid
+ WHEN MATCHED THEN
+ UPDATE SET tid = tid + 1, balance = balance + delta, val = val || ' updated by merge'
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (sid, delta, 'inserted by merge');
+SELECT * FROM pa_target ORDER BY tid;
+ROLLBACK;
+
+DROP TABLE pa_target CASCADE;
+
+-- The target table is partitioned in the same way, but this time by attaching
+-- partitions which have columns in different order, dropped columns etc.
+CREATE TABLE pa_target (tid integer, balance float, val text)
+ PARTITION BY LIST (tid);
+CREATE TABLE part1 (tid integer, balance float, val text);
+CREATE TABLE part2 (balance float, tid integer, val text);
+CREATE TABLE part3 (tid integer, balance float, val text);
+CREATE TABLE part4 (extraid text, tid integer, balance float, val text);
+ALTER TABLE part4 DROP COLUMN extraid;
+
+ALTER TABLE pa_target ATTACH PARTITION part1 FOR VALUES IN (1,4);
+ALTER TABLE pa_target ATTACH PARTITION part2 FOR VALUES IN (2,5,6);
+ALTER TABLE pa_target ATTACH PARTITION part3 FOR VALUES IN (3,8,9);
+ALTER TABLE pa_target ATTACH PARTITION part4 DEFAULT;
+
+-- insert a few rows in the target table (odd numbered tid)
+INSERT INTO pa_target SELECT id, id * 100, 'initial' FROM generate_series(1,14,2) AS id;
+
+-- try simple MERGE
+BEGIN;
+MERGE INTO pa_target t
+ USING pa_source s
+ ON t.tid = s.sid
+ WHEN MATCHED THEN
+ UPDATE SET balance = balance + delta, val = val || ' updated by merge'
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (sid, delta, 'inserted by merge');
+SELECT * FROM pa_target ORDER BY tid;
+ROLLBACK;
+
+-- same with a constant qual
+BEGIN;
+MERGE INTO pa_target t
+ USING pa_source s
+ ON t.tid = s.sid AND tid = 1
+ WHEN MATCHED THEN
+ UPDATE SET balance = balance + delta, val = val || ' updated by merge'
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (sid, delta, 'inserted by merge');
+SELECT * FROM pa_target ORDER BY tid;
+ROLLBACK;
+
+-- try updating the partition key column
+BEGIN;
+MERGE INTO pa_target t
+ USING pa_source s
+ ON t.tid = s.sid
+ WHEN MATCHED THEN
+ UPDATE SET tid = tid + 1, balance = balance + delta, val = val || ' updated by merge'
+ WHEN NOT MATCHED THEN
+ INSERT VALUES (sid, delta, 'inserted by merge');
+SELECT * FROM pa_target ORDER BY tid;
+ROLLBACK;
+
+DROP TABLE pa_source;
+DROP TABLE pa_target CASCADE;
+
+-- some complex joins on the source side
+
+CREATE TABLE cj_target (tid integer, balance float, val text);
+CREATE TABLE cj_source1 (sid1 integer, scat integer, delta integer);
+CREATE TABLE cj_source2 (sid2 integer, sval text);
+INSERT INTO cj_source1 VALUES (1, 10, 100);
+INSERT INTO cj_source1 VALUES (1, 20, 200);
+INSERT INTO cj_source1 VALUES (2, 20, 300);
+INSERT INTO cj_source1 VALUES (3, 10, 400);
+INSERT INTO cj_source2 VALUES (1, 'initial source2');
+INSERT INTO cj_source2 VALUES (2, 'initial source2');
+INSERT INTO cj_source2 VALUES (3, 'initial source2');
+
+-- source relation is an unalised join
+MERGE INTO cj_target t
+USING cj_source1 s1
+ INNER JOIN cj_source2 s2 ON sid1 = sid2
+ON t.tid = sid1
+WHEN NOT MATCHED THEN
+ INSERT VALUES (sid1, delta, sval);
+
+-- try accessing columns from either side of the source join
+MERGE INTO cj_target t
+USING cj_source2 s2
+ INNER JOIN cj_source1 s1 ON sid1 = sid2 AND scat = 20
+ON t.tid = sid1
+WHEN NOT MATCHED THEN
+ INSERT VALUES (sid2, delta, sval)
+WHEN MATCHED THEN
+ DELETE;
+
+-- some simple expressions in INSERT targetlist
+MERGE INTO cj_target t
+USING cj_source2 s2
+ INNER JOIN cj_source1 s1 ON sid1 = sid2
+ON t.tid = sid1
+WHEN NOT MATCHED THEN
+ INSERT VALUES (sid2, delta + scat, sval)
+WHEN MATCHED THEN
+ UPDATE SET val = val || ' updated by merge';
+
+MERGE INTO cj_target t
+USING cj_source2 s2
+ INNER JOIN cj_source1 s1 ON sid1 = sid2 AND scat = 20
+ON t.tid = sid1
+WHEN MATCHED THEN
+ UPDATE SET val = val || ' ' || delta::text;
+
+SELECT * FROM cj_target;
+DROP TABLE cj_source2, cj_source1, cj_target;
+
+-- SERIALIZABLE test
+-- handled in isolation tests
+
+-- prepare
+
+RESET SESSION AUTHORIZATION;
+DROP TABLE target, target2;
+DROP TABLE source, source2;
+DROP FUNCTION merge_trigfunc();
+DROP USER merge_privs;
+DROP USER merge_no_privs;
diff --git a/src/test/regress/sql/rowsecurity.sql b/src/test/regress/sql/rowsecurity.sql
index f3a31db..480ec34 100644
--- a/src/test/regress/sql/rowsecurity.sql
+++ b/src/test/regress/sql/rowsecurity.sql
@@ -813,6 +813,130 @@ INSERT INTO document VALUES (1, (SELECT cid from category WHERE cname = 'novel')
ON CONFLICT (did) DO UPDATE SET dauthor = 'regress_rls_carol';
--
+-- MERGE
+--
+RESET SESSION AUTHORIZATION;
+DROP POLICY p3_with_all ON document;
+
+ALTER TABLE document ADD COLUMN dnotes text DEFAULT '';
+-- all documents are readable
+CREATE POLICY p1 ON document FOR SELECT USING (true);
+-- one may insert documents only authored by them
+CREATE POLICY p2 ON document FOR INSERT WITH CHECK (dauthor = current_user);
+-- one may only update documents in 'novel' category
+CREATE POLICY p3 ON document FOR UPDATE
+ USING (cid = (SELECT cid from category WHERE cname = 'novel'))
+ WITH CHECK (dauthor = current_user);
+-- one may only delete documents in 'manga' category
+CREATE POLICY p4 ON document FOR DELETE
+ USING (cid = (SELECT cid from category WHERE cname = 'manga'));
+
+SELECT * FROM document;
+
+SET SESSION AUTHORIZATION regress_rls_bob;
+
+-- Fails, since update violates WITH CHECK qual on dauthor
+MERGE INTO document d
+USING (SELECT 1 as sdid) s
+ON did = s.sdid
+WHEN MATCHED THEN
+ UPDATE SET dnotes = dnotes || ' notes added by merge1 ', dauthor = 'regress_rls_alice';
+
+-- Should be OK since USING and WITH CHECK quals pass
+MERGE INTO document d
+USING (SELECT 1 as sdid) s
+ON did = s.sdid
+WHEN MATCHED THEN
+ UPDATE SET dnotes = dnotes || ' notes added by merge2 ';
+
+-- Even when dauthor is updated explicitly, but to the existing value
+MERGE INTO document d
+USING (SELECT 1 as sdid) s
+ON did = s.sdid
+WHEN MATCHED THEN
+ UPDATE SET dnotes = dnotes || ' notes added by merge3 ', dauthor = 'regress_rls_bob';
+
+-- There is a MATCH for did = 3, but UPDATE's USING qual does not allow
+-- updating an item in category 'science fiction'
+MERGE INTO document d
+USING (SELECT 3 as sdid) s
+ON did = s.sdid
+WHEN MATCHED THEN
+ UPDATE SET dnotes = dnotes || ' notes added by merge ';
+
+-- The same thing with DELETE action, but fails again because no permissions
+-- to delete items in 'science fiction' category that did 3 belongs to.
+MERGE INTO document d
+USING (SELECT 3 as sdid) s
+ON did = s.sdid
+WHEN MATCHED THEN
+ DELETE;
+
+-- Document with did 4 belongs to 'manga' category which is allowed for
+-- deletion. But this fails because the UPDATE action is matched first and
+-- UPDATE policy does not allow updation in the category.
+MERGE INTO document d
+USING (SELECT 4 as sdid) s
+ON did = s.sdid
+WHEN MATCHED AND dnotes = '' THEN
+ UPDATE SET dnotes = dnotes || ' notes added by merge '
+WHEN MATCHED THEN
+ DELETE;
+
+-- UPDATE action is not matched this time because of the WHEN AND qual.
+-- DELETE still fails because role regress_rls_bob does not have SELECT
+-- privileges on 'manga' category row in the category table.
+MERGE INTO document d
+USING (SELECT 4 as sdid) s
+ON did = s.sdid
+WHEN MATCHED AND dnotes <> '' THEN
+ UPDATE SET dnotes = dnotes || ' notes added by merge '
+WHEN MATCHED THEN
+ DELETE;
+
+SELECT * FROM document WHERE did = 4;
+
+-- Switch to regress_rls_carol role and try the DELETE again. It should succeed
+-- this time
+RESET SESSION AUTHORIZATION;
+SET SESSION AUTHORIZATION regress_rls_carol;
+
+MERGE INTO document d
+USING (SELECT 4 as sdid) s
+ON did = s.sdid
+WHEN MATCHED AND dnotes <> '' THEN
+ UPDATE SET dnotes = dnotes || ' notes added by merge '
+WHEN MATCHED THEN
+ DELETE;
+
+-- Switch back to regress_rls_bob role
+RESET SESSION AUTHORIZATION;
+SET SESSION AUTHORIZATION regress_rls_bob;
+
+-- Try INSERT action. This fails because we are trying to insert
+-- dauthor = regress_rls_dave and INSERT's WITH CHECK does not allow
+-- that
+MERGE INTO document d
+USING (SELECT 12 as sdid) s
+ON did = s.sdid
+WHEN MATCHED THEN
+ DELETE
+WHEN NOT MATCHED THEN
+ INSERT VALUES (12, 11, 1, 'regress_rls_dave', 'another novel');
+
+-- This should be fine
+MERGE INTO document d
+USING (SELECT 12 as sdid) s
+ON did = s.sdid
+WHEN MATCHED THEN
+ DELETE
+WHEN NOT MATCHED THEN
+ INSERT VALUES (12, 11, 1, 'regress_rls_bob', 'another novel');
+
+-- Just check everything went per plan
+SELECT * FROM document;
+
+--
-- ROLE/GROUP
--
SET SESSION AUTHORIZATION regress_rls_alice;