*** a/doc/src/sgml/func.sgml
--- b/doc/src/sgml/func.sgml
***************
*** 10061,10066 **** SELECT count(*) FROM sometable;
--- 10061,10297 ----
+
+ Window Functions
+
+
+ Window functions provide facilities of
+ windowed table calculation, including window aggregate.
+
+ The built-in window functions are listed in
+ .
+ All of aggregate functions in and
+ can be also used in
+ the windowed table.
+
+
+
+ General-Purpose Window Functions
+
+
+
+
+ Function
+ Argument Type
+ Return Type
+ Description
+
+
+
+
+
+
+
+ rank
+
+ rank()
+
+
+
+ bigint
+
+ number of the row from 1 ordered by sort_expressions in the partition, with gaps
+
+
+
+
+
+ dense_rank
+
+ dense_rank()
+
+
+
+ bigint
+
+ number of the row from 1 ordered by sort_expressions in the partition, without gaps
+
+
+
+
+
+ row_number()
+
+ row_number()
+
+
+
+ bigint
+
+ number of the row from 1 ordered by sort_expressions in the partition, incrementing always
+
+
+
+
+
+ percent_rank()
+
+ percent_rank()
+
+
+
+ double precision
+
+ relative rank of the row between 0 and 1 ordered by sort_expressions in the partition, with gap
+
+
+
+
+
+ cume_dist()
+
+ cume_dist()
+
+
+
+ double precision
+
+ relative rank of the row between 0 and 1 ordered by sort_expressions in the partition, without gap
+
+
+
+
+
+ ntile()
+
+ ntile(integer)
+
+
+ integer
+
+
+ integer
+
+ integer value ranging from 1 to the argument integer, equally dividing the partition
+
+
+
+
+
+ lag
+
+
+ lag(value, offset, [default])
+
+
+
+ any, integer[, any]
+
+
+ same type as value
+
+
+ returns value evaluated on
+ the row that is offset number of
+ rows before the current row within the partition. If default is specified and the target row is out
+ of the partition, default is returned.
+
+
+
+
+
+
+ lead
+
+
+ lead(value, offset, [default])
+
+
+
+ any, integer[, any]
+
+
+ same type as value
+
+
+ returns value evaluated on
+ the row that is offset number of
+ rows after the current row within the partition. If default is specified and the target row is out
+ of the partition, default is returned.
+
+
+
+
+
+
+ first_value
+
+ first_value(value)
+
+
+ any
+
+
+ same type as value
+
+
+ returns value evaluated on the row
+ that is the first row of the frame
+
+
+
+
+
+
+ last_value
+
+ last_value(value)
+
+
+ any
+
+
+ same type as value
+
+
+ returns value evaluated on the row
+ that is the last row of the frame
+
+
+
+
+
+
+ nth_value
+
+
+ nth_value(value, nth)
+
+
+
+ any, integer
+
+
+ same type as value
+
+
+ returns value evaluated on the row
+ that is the nth row of the
+ frame
+
+
+
+
+
+
+
Subquery Expressions
*** a/doc/src/sgml/keywords.sgml
--- b/doc/src/sgml/keywords.sgml
***************
*** 1510,1516 ****
EXCLUDE
!
non-reserved
--- 1510,1516 ----
EXCLUDE
! non-reserved
non-reserved
***************
*** 2868,2874 ****
OTHERS
!
non-reserved
--- 2868,2874 ----
OTHERS
! non-reserved
non-reserved
***************
*** 2896,2902 ****
OVER
!
reserved
--- 2896,2902 ----
OVER
! reserved
reserved
***************
*** 3015,3021 ****
PARTITION
!
reserved
--- 3015,3021 ----
PARTITION
! non-reserved
reserved
***************
*** 3106,3112 ****
PRECEDING
!
non-reserved
--- 3106,3112 ----
PRECEDING
! reserved
non-reserved
***************
*** 3204,3210 ****
RANGE
!
reserved
--- 3204,3210 ----
RANGE
! reserved
reserved
***************
*** 4128,4134 ****
TIES
!
non-reserved
--- 4128,4134 ----
TIES
! non-reserved
non-reserved
***************
*** 4317,4323 ****
UNBOUNDED
!
non-reserved
--- 4317,4323 ----
UNBOUNDED
! non-reserved
non-reserved
***************
*** 4590,4596 ****
WINDOW
!
reserved
--- 4590,4596 ----
WINDOW
! reserved
reserved
*** a/doc/src/sgml/queries.sgml
--- b/doc/src/sgml/queries.sgml
***************
*** 950,955 **** SELECT product_id, p.name, (sum(s.units) * (p.price - p.cost)) AS profit
--- 950,1017 ----
to be the same in all parts of the query.
+
+
+ The <literal>WINDOW</literal> Clauses
+
+
+ WINDOW
+
+
+
+ windowing
+
+
+
+ After WHERE and GROUP BY process,
+ rows might be windowed table, using the WINDOW
+ clause.
+
+
+
+ SELECT function_call OVER
+ (window_specification)
+ FROM ...
+
+ SELECT function_call OVER window_name
+ FROM ...
+ WHERE ...
+ GROUP BY ...
+ HAVING ...
+ WINDOW window_name AS (window_specification)
+
+
+
+ where window_specification is given as:
+
+
+
+ PARTITION BY partition_expression ORDER BY sort_expression
+
+
+
+ The WINDOW clause specifies what kind of window can be used in the
+ . Since window
+ functions can specify its own window with OVER clause, no WINDOW
+ clause may be needed even if the SELECT list has window functions.
+ But when more than one function specify the same window specification,
+ the WINDOW clause saves complexed SQL command.
+
+
+
+ Windowing operations are sometimes done with sort operations. If you
+ need exact ordered result as the final output, you must specify
+ ORDER BY clause. Also, it is better that you don't
+ assume any ordered result based on the subquery or physical table
+ placement.
+
+
+
+ If there is window_name that isn't referred by
+ any window functions in the WINDOW clause, the
+ window_specification is only ignored.
+
+
*** a/doc/src/sgml/query.sgml
--- b/doc/src/sgml/query.sgml
***************
*** 805,810 **** SELECT city, max(temp_lo)
--- 805,970 ----
+
+ Window Functions
+
+
+ A window function is the operation across a set of rows in
+ a windowed table. This may sound similar to aggregate functions,
+ but contrast to that window functions don't reduce rows.
+ Additionally, window functions can compute different results
+ row by row.
+
+
+
+ Here is an example that shows how to compare each employee's salary
+ with the department average salary.
+
+
+ SELECT depname, empno, salary, avg(salary) OVER (PARTITION BY depname) FROM empsalary;
+
+
+
+ depname | empno | salary | avg
+ -----------+-------+--------+-----------------------
+ develop | 11 | 5200 | 5020.0000000000000000
+ develop | 7 | 4200 | 5020.0000000000000000
+ develop | 9 | 4500 | 5020.0000000000000000
+ develop | 8 | 6000 | 5020.0000000000000000
+ develop | 10 | 5200 | 5020.0000000000000000
+ personnel | 5 | 3500 | 3700.0000000000000000
+ personnel | 2 | 3900 | 3700.0000000000000000
+ sales | 3 | 4800 | 4866.6666666666666667
+ sales | 1 | 5000 | 4866.6666666666666667
+ sales | 4 | 4800 | 4866.6666666666666667
+ (10 rows)
+
+
+ avg works exact same as the aggregate functions
+ except it doesn't reduce rows and returns same result within the
+ same depname. Without reducing rows,
+ it is possible to compare the original salary
+ with each department's average salary.
+
+
+
+ Another expample shows different capability of window functions
+ from above.
+
+
+ SELECT depname, empno, salary, rank() OVER (PARTITION BY depname ORDER BY salary DESC) FROM empsalary;
+
+
+
+ depname | empno | salary | rank
+ -----------+-------+--------+------
+ develop | 8 | 6000 | 1
+ develop | 10 | 5200 | 2
+ develop | 11 | 5200 | 2
+ develop | 9 | 4500 | 4
+ develop | 7 | 4200 | 5
+ personnel | 2 | 3900 | 1
+ personnel | 5 | 3500 | 2
+ sales | 1 | 5000 | 1
+ sales | 4 | 4800 | 2
+ sales | 3 | 4800 | 2
+ (10 rows)
+
+
+ rank returns offset position of the row when
+ the rows in the partition are ordered by the specified value. In this case,
+ in each department each employee's salary rank with gap is shown.
+
+
+
+ In addition to partition there is another concept called
+ frame as a set of rows. Currently frame can
+ only be specified by ORDER BY clause.
+
+
+
+ SELECT salary, sum(salary) OVER() FROM empsalary;
+
+
+
+ salary | sum
+ --------+-------
+ 5200 | 47100
+ 5000 | 47100
+ 3500 | 47100
+ 4800 | 47100
+ 3900 | 47100
+ 4200 | 47100
+ 4500 | 47100
+ 4800 | 47100
+ 6000 | 47100
+ 5200 | 47100
+ (10 rows)
+
+
+
+ The example above has a frame that contains all rows of
+ the partition. Since window aggregate functions collects
+ all rows contained in the frame, the results of each
+ row is sum of the all salary.
+
+
+
+ SELECT salary, sum(salary) OVER(ORDER BY salary) FROM empsalary;
+
+
+
+ salary | sum
+ --------+-------
+ 3500 | 3500
+ 3900 | 7400
+ 4200 | 11600
+ 4500 | 16100
+ 4800 | 20900
+ 4800 | 25700
+ 5000 | 30700
+ 5200 | 35900
+ 5200 | 41100
+ 6000 | 47100
+ (10 rows)
+
+
+
+ Contrast to that example, this one specifies ORDER BY explicitly,
+ and there is a frame including rows that is returned between
+ the first row and the current row. So the results of the sum
+ is cumulative total from the first row. This is because the frame
+ contains not all the rows in the partition.
+
+
+
+ Window functions are put in the SELECT list.
+ It is forbidden anywhere else such as GROUP BY,
+ HAVING and WHERE clauses.
+ The arguments passed to window functions and the expressions in
+ PARTITION BY and ORDER BY
+ of a window definition can be the results of aggregate functions.
+ But window functions may not be placed as aggregate functions'
+ arguments. All of window functions are evaluated after aggregate.
+
+
+
+ In a query, windows can be defined as many as needed. The order
+ of the evaluation for each window is implicitly determined by
+ backend, which means there is no way to predict its order.
+
+
+
+ The same window definitions can be named and put togather into one
+ definition using .
+
+
+ SELECT sum(salary) OVER w, avg(salary) OVER w FROM empsalary WINDOW w AS (PARTITION BY depname);
+
+
+ The two of functions are evaluated in the same window.
+
+
Updates
*** a/doc/src/sgml/ref/select.sgml
--- b/doc/src/sgml/ref/select.sgml
***************
*** 27,32 **** SELECT [ ALL | DISTINCT [ ON ( expressioncondition ]
[ GROUP BY expression [, ...] ]
[ HAVING condition [, ...] ]
+ [ WINDOW window_name AS ( window_definition ) [, ...] ]
[ { UNION | INTERSECT | EXCEPT } [ ALL ] select ]
[ ORDER BY expression [ ASC | DESC | USING operator ] [ NULLS { FIRST | LAST } ] [, ...] ]
[ LIMIT { count | ALL } ]
***************
*** 552,557 **** HAVING condition
--- 553,590 ----
+
+ <literal>WINDOW</literal> Clause
+
+
+ The optional WINDOW clause has the general form
+
+ WINDOW window_name AS (window_definition) [, ...]
+
+ where window_name is
+ the window name that is referred from windowed functions, and
+ window_definition is described as follows:
+
+
+ [ PARTITION BY expression [, ...] ]
+ [ ORDER BY expression [ ASC | DESC | USING operator ] [ NULLS { FIRST | LAST } ] [, ...] ]
+
+ where the first expression is the same as
+ one in GROUP BY and the second is the same as
+ one in ORDER BY of the SELECT.
+ Both of these can be omitted.
+
+
+
+ When the window functions with OVER clause in the
+ SELECT list refers to a window name, WINDOW
+ clause must describe what the windowed table is like. If some of the
+ window names are not referred from any of the window function calls,
+ they will be just ignored. In the window definition the
+ expressions are allowed to be aggregated.
+
+
+
<command>SELECT</command> List
*** a/doc/src/sgml/syntax.sgml
--- b/doc/src/sgml/syntax.sgml
***************
*** 1539,1544 **** sqrt(2)
--- 1539,1596 ----
+
+ Windowed Tables
+
+
+ A windowed table is a table with one or more windows.
+ A window is a transient set of rows split within a table
+ described by a window definition. The windowed table allows
+ to process values across multiple rows within the window.
+
+
+
+ The windowed table comes with window function calls.
+
+
+ function_call ([arg]) OVER (PARTITION BY partition_column [ , ... ] ORDER BY order_column [ , ... ])
+ function_call ([arg]) OVER window_name
+
+
+ where arg,
+ partition_column and
+ order_column are normal target
+ list such as table column and subquery result as well as
+ the result of GROUP BY process. Either
+ PARTITION clause or
+ ORDER clause must be specified in a
+ window definition. The window_name
+ in the second form indicates use of a window that is defined
+ later WINDOW clause. In the windowed tables
+ any of aggregate function can be called. Additionally predefined
+ window functions may be used to calculate rank values.
+
+
+
+ The predefined ranking window functions are described in
+ . Currently, window functions
+ cannot be defined by the user.
+
+
+
+ Windowed functions doesn't accept DISTINCT and ALL syntax, even though
+ the function is an aggregate function.
+
+
+
+ Windowed functions are not placed in any of GROUP BY, HAVING and
+ WHERE clauses, which process values before any of the windows. If
+ there is need to qualify rows by the result of windowed functions,
+ whole of the query must be nested and append WHERE clause outer of
+ the current query.
+
+
+
Type Casts
*** a/src/backend/catalog/pg_aggregate.c
--- b/src/backend/catalog/pg_aggregate.c
***************
*** 294,299 **** lookup_agg_function(List *fnName,
--- 294,301 ----
Oid fnOid;
bool retset;
int nvargs;
+ bool isagg;
+ bool iswfunc;
Oid *true_oid_array;
FuncDetailCode fdresult;
AclResult aclresult;
***************
*** 308,313 **** lookup_agg_function(List *fnName,
--- 310,316 ----
*/
fdresult = func_get_detail(fnName, NIL, nargs, input_types, false,
&fnOid, rettype, &retset, &nvargs,
+ &isagg, &iswfunc,
&true_oid_array);
/* only valid case is a normal function not returning a set */
*** a/src/backend/catalog/pg_proc.c
--- b/src/backend/catalog/pg_proc.c
***************
*** 290,295 **** ProcedureCreate(const char *procedureName,
--- 290,296 ----
values[Anum_pg_proc_prorows - 1] = Float4GetDatum(prorows);
values[Anum_pg_proc_provariadic - 1] = ObjectIdGetDatum(variadicType);
values[Anum_pg_proc_proisagg - 1] = BoolGetDatum(isAgg);
+ values[Anum_pg_proc_proiswfunc - 1] = BoolGetDatum(false); /* temporarily */
values[Anum_pg_proc_prosecdef - 1] = BoolGetDatum(security_definer);
values[Anum_pg_proc_proisstrict - 1] = BoolGetDatum(isStrict);
values[Anum_pg_proc_proretset - 1] = BoolGetDatum(returnsSet);
*** a/src/backend/commands/explain.c
--- b/src/backend/commands/explain.c
***************
*** 626,631 **** explain_outNode(StringInfo str,
--- 626,634 ----
case T_Limit:
pname = "Limit";
break;
+ case T_Window:
+ pname = "Window";
+ break;
case T_Hash:
pname = "Hash";
break;
***************
*** 912,917 **** explain_outNode(StringInfo str,
--- 915,922 ----
show_sort_info((SortState *) planstate,
str, indent, es);
break;
+ case T_Window:
+ break;
case T_Result:
show_upper_qual((List *) ((Result *) plan)->resconstantqual,
"One-Time Filter", plan,
*** a/src/backend/executor/Makefile
--- b/src/backend/executor/Makefile
***************
*** 20,26 **** OBJS = execAmi.o execCurrent.o execGrouping.o execJunk.o execMain.o \
nodeHashjoin.o nodeIndexscan.o nodeMaterial.o nodeMergejoin.o \
nodeNestloop.o nodeFunctionscan.o nodeRecursiveunion.o nodeResult.o \
nodeSeqscan.o nodeSetOp.o nodeSort.o nodeUnique.o \
! nodeValuesscan.o nodeCtescan.o nodeWorktablescan.o \
nodeLimit.o nodeGroup.o nodeSubplan.o nodeSubqueryscan.o nodeTidscan.o \
tstoreReceiver.o spi.o
--- 20,26 ----
nodeHashjoin.o nodeIndexscan.o nodeMaterial.o nodeMergejoin.o \
nodeNestloop.o nodeFunctionscan.o nodeRecursiveunion.o nodeResult.o \
nodeSeqscan.o nodeSetOp.o nodeSort.o nodeUnique.o \
! nodeValuesscan.o nodeCtescan.o nodeWindow.o nodeWorktablescan.o \
nodeLimit.o nodeGroup.o nodeSubplan.o nodeSubqueryscan.o nodeTidscan.o \
tstoreReceiver.o spi.o
*** a/src/backend/executor/execAmi.c
--- b/src/backend/executor/execAmi.c
***************
*** 42,47 ****
--- 42,48 ----
#include "executor/nodeValuesscan.h"
#include "executor/nodeCtescan.h"
#include "executor/nodeWorktablescan.h"
+ #include "executor/nodeWindow.h"
#include "nodes/nodeFuncs.h"
#include "utils/syscache.h"
***************
*** 226,231 **** ExecReScan(PlanState *node, ExprContext *exprCtxt)
--- 227,236 ----
ExecReScanLimit((LimitState *) node, exprCtxt);
break;
+ case T_WindowState:
+ ExecReScanWindow((WindowState *) node, exprCtxt);
+ break;
+
default:
elog(ERROR, "unrecognized node type: %d", (int) nodeTag(node));
break;
*** a/src/backend/executor/execGrouping.c
--- b/src/backend/executor/execGrouping.c
***************
*** 16,21 ****
--- 16,22 ----
#include "executor/executor.h"
#include "parser/parse_oper.h"
+ #include "utils/builtins.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/syscache.h"
***************
*** 565,567 **** TupleHashTableMatch(const void *key1, const void *key2, Size keysize)
--- 566,589 ----
else
return 1;
}
+
+ /*
+ * GetAggInitVal
+ * return datum represented by textInitVal.
+ */
+ Datum
+ GetAggInitVal(Datum textInitVal, Oid transtype)
+ {
+ Oid typinput,
+ typioparam;
+ char *strInitVal;
+ Datum initVal;
+
+ getTypeInputInfo(transtype, &typinput, &typioparam);
+ strInitVal = TextDatumGetCString(textInitVal);
+ initVal = OidInputFunctionCall(typinput, strInitVal,
+ typioparam, -1);
+ pfree(strInitVal);
+ return initVal;
+ }
+
*** a/src/backend/executor/execProcnode.c
--- b/src/backend/executor/execProcnode.c
***************
*** 106,111 ****
--- 106,112 ----
#include "executor/nodeValuesscan.h"
#include "executor/nodeCtescan.h"
#include "executor/nodeWorktablescan.h"
+ #include "executor/nodeWindow.h"
#include "miscadmin.h"
***************
*** 280,285 **** ExecInitNode(Plan *node, EState *estate, int eflags)
--- 281,291 ----
estate, eflags);
break;
+ case T_Window:
+ result = (PlanState *) ExecInitWindow((Window *) node,
+ estate, eflags);
+ break;
+
default:
elog(ERROR, "unrecognized node type: %d", (int) nodeTag(node));
result = NULL; /* keep compiler quiet */
***************
*** 441,446 **** ExecProcNode(PlanState *node)
--- 447,456 ----
result = ExecLimit((LimitState *) node);
break;
+ case T_WindowState:
+ result = ExecWindow((WindowState *) node);
+ break;
+
default:
elog(ERROR, "unrecognized node type: %d", (int) nodeTag(node));
result = NULL;
***************
*** 613,618 **** ExecCountSlotsNode(Plan *node)
--- 623,632 ----
case T_Limit:
return ExecCountSlotsLimit((Limit *) node);
+ case T_Window:
+ return ExecCountSlotsWindow((Window *) node);
+ break;
+
default:
elog(ERROR, "unrecognized node type: %d", (int) nodeTag(node));
break;
***************
*** 765,770 **** ExecEndNode(PlanState *node)
--- 779,788 ----
ExecEndLimit((LimitState *) node);
break;
+ case T_WindowState:
+ ExecEndWindow((WindowState *) node);
+ break;
+
default:
elog(ERROR, "unrecognized node type: %d", (int) nodeTag(node));
break;
*** a/src/backend/executor/execQual.c
--- b/src/backend/executor/execQual.c
***************
*** 62,67 **** static Datum ExecEvalArrayRef(ArrayRefExprState *astate,
--- 62,70 ----
static Datum ExecEvalAggref(AggrefExprState *aggref,
ExprContext *econtext,
bool *isNull, ExprDoneCond *isDone);
+ static Datum ExecEvalWFunc(WFuncExprState *wfunc,
+ ExprContext *econtext,
+ bool *isNull, ExprDoneCond *isDone);
static Datum ExecEvalVar(ExprState *exprstate, ExprContext *econtext,
bool *isNull, ExprDoneCond *isDone);
static Datum ExecEvalScalarVar(ExprState *exprstate, ExprContext *econtext,
***************
*** 444,449 **** ExecEvalAggref(AggrefExprState *aggref, ExprContext *econtext,
--- 447,476 ----
}
/* ----------------------------------------------------------------
+ * ExecEvalWFunc
+ *
+ * Returns a Datum whose value is the value of the precomputed
+ * window function found in the given expression context.
+ *
+ * Note: WFunc uses ecxt_aggvalues for stored result
+ * because Window node never contains Aggref node.
+ * ----------------------------------------------------------------
+ */
+ static Datum
+ ExecEvalWFunc(WFuncExprState *wfunc, ExprContext *econtext,
+ bool *isNull, ExprDoneCond *isDone)
+ {
+ if (isDone)
+ *isDone = ExprSingleResult;
+
+ if (econtext->ecxt_aggvalues == NULL) /* safety check */
+ elog(ERROR, "no aggregates in this expression context");
+
+ *isNull = econtext->ecxt_aggnulls[wfunc->funcno];
+ return econtext->ecxt_aggvalues[wfunc->funcno];
+ }
+
+ /* ----------------------------------------------------------------
* ExecEvalVar
*
* Returns a Datum whose value is the value of a range
***************
*** 4140,4145 **** ExecInitExpr(Expr *node, PlanState *parent)
--- 4167,4214 ----
state = (ExprState *) astate;
}
break;
+ case T_WFunc:
+ {
+ WFunc *wfunc = (WFunc *) node;
+ WFuncExprState *wfstate = makeNode(WFuncExprState);
+
+ wfstate->xprstate.evalfunc = (ExprStateEvalFunc) ExecEvalWFunc;
+ if (parent && IsA(parent, WindowState))
+ {
+ WindowState *winstate = (WindowState *) parent;
+ int nfuncs = winstate->numfuncs,
+ naggs = winstate->numaggs;
+
+ winstate->funcs = lcons(wfstate, winstate->funcs);
+ nfuncs = ++winstate->numfuncs;
+ if(wfunc->pure_agg)
+ naggs = ++winstate->numaggs;
+
+ wfstate->args = (List *) ExecInitExpr((Expr *) wfunc->args,
+ parent);
+ /*
+ * Complain if the wfunc's arguments contain any
+ * wfuncs; nested agg functions are semantically
+ * nonsensical. (This should have been caught earlier,
+ * but we defend against it here anyway.)
+ */
+ if (nfuncs != winstate->numfuncs)
+ ereport(ERROR,
+ (errcode(ERRCODE_WINDOWING_ERROR),
+ errmsg("window function calls cannot be nested")));
+ if (naggs != winstate->numaggs)
+ ereport(ERROR,
+ (errcode(ERRCODE_WINDOWING_ERROR),
+ errmsg("window function calls cannot be nested")));
+ }
+ else
+ {
+ /* planner messed up */
+ elog(ERROR, "wfunc found in non-Window plan node");
+ }
+ state = (ExprState *) wfstate;
+ }
+ break;
case T_ArrayRef:
{
ArrayRef *aref = (ArrayRef *) node;
*** a/src/backend/executor/nodeAgg.c
--- b/src/backend/executor/nodeAgg.c
***************
*** 233,239 **** static AggHashEntry lookup_hash_entry(AggState *aggstate,
static TupleTableSlot *agg_retrieve_direct(AggState *aggstate);
static void agg_fill_hash_table(AggState *aggstate);
static TupleTableSlot *agg_retrieve_hash_table(AggState *aggstate);
- static Datum GetAggInitVal(Datum textInitVal, Oid transtype);
/*
--- 233,238 ----
***************
*** 1586,1607 **** ExecInitAgg(Agg *node, EState *estate, int eflags)
return aggstate;
}
- static Datum
- GetAggInitVal(Datum textInitVal, Oid transtype)
- {
- Oid typinput,
- typioparam;
- char *strInitVal;
- Datum initVal;
-
- getTypeInputInfo(transtype, &typinput, &typioparam);
- strInitVal = TextDatumGetCString(textInitVal);
- initVal = OidInputFunctionCall(typinput, strInitVal,
- typioparam, -1);
- pfree(strInitVal);
- return initVal;
- }
-
int
ExecCountSlotsAgg(Agg *node)
{
--- 1585,1590 ----
*** /dev/null
--- b/src/backend/executor/nodeWindow.c
***************
*** 0 ****
--- 1,2396 ----
+ /*-------------------------------------------------------------------------
+ *
+ * nodeWindow.c
+ *
+ * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * Window node evaluates only WFunc expression. Any other expressions are
+ * retrieved from the outer plan as Var or Const node. This is based on
+ * the fact window functions may evaluate those nodes more than once.
+ * The node collects rows into its WindowObject based on its row buffering
+ * strategy, which is classified into three; Row, Frame and Partition.
+ * Strategy requirement depends on types of desparate window functions.
+ * Each function declares somehow (currently macro in .c source code) which
+ * buffering is needed, decided by the usage of window function APIs.
+ * If a function chooses Row buffering, it is allowed to use WinRowXXX APIs
+ * and if Frame buffering, allowed to use WinRowXXX and WinFrameXXX, and if
+ * Partition buffering allowed to use WinRowXXX, WinFrameXXX and WinPartXXX.
+ * This mechanism avoids to store unused rows, which would be very expensive
+ * if the number of buffered rows got huge.
+ *
+ * The Row and Partition bufferings is relatively easy to operate, whereas
+ * Frame is hard because it may move within the partition. If the frame
+ * cuts off some preceding rows we call it "to shrink", and if the frame
+ * feeds in some following rows we call it "to extend". A moving frame
+ * moves shrinking and extending rows when the current row advances.
+ *
+ * A window function is defined as a function maked as wfunc in pg_proc. By this
+ * mark, it means the function can handle window function APIs that allow
+ * it to access arbitrary random rows within the window.
+ *
+ * Window node can aggregate function as well, treating it as special case.
+ * The aggregated result is cached in a WindowStatePerAgg struct and is
+ * recycled if the frame wasn't either shrinked nor extended. If not shrinked
+ * but extended, the unprocessed rows are passed to trans function and the result
+ * would be finalized again. If not shrinked and not extended, the result is
+ * reused without additional trans/final function calls. If shrinked, the cached
+ * result values cannot be used so the node initializes state and
+ * aggregate values from the head of the frame again. This is not efficient
+ * so the aggregate function can be a window function, which can subtract
+ * values from the shrinking rows for the next execution, in order to avoid
+ * whole the aggregate process is processed again. fcinfo->context will be
+ * a WindowState instead of AggState if the aggregate function is called as
+ * a window function.
+ *
+ * Currently Window node assume its input is sorted appropriately so it doesn't
+ * care sort operation. It may be optimized by HashTable or something, which
+ * is regarded as advanced challenges so we don't touch it for the first version.
+ *
+ * Note that the solid concept of the window functions is "they can access
+ * arbitrary rows within the frame as they want". As far as we keep the rule
+ * of thumb, any kind of optimization is allowed.
+ *
+ * IDENTIFICATION
+ * $Id$
+ *
+ *-------------------------------------------------------------------------
+ */
+
+ #include "postgres.h"
+
+ #include "catalog/pg_aggregate.h"
+ #include "catalog/pg_proc.h"
+ #include "catalog/pg_type.h"
+ #include "executor/executor.h"
+ #include "executor/nodeWindow.h"
+ #include "miscadmin.h"
+ #include "nodes/nodeFuncs.h"
+ #include "optimizer/clauses.h"
+ #include "parser/parse_agg.h"
+ #include "parser/parse_coerce.h"
+ #include "parser/parse_expr.h"
+ #include "parser/parse_oper.h"
+ #include "utils/acl.h"
+ #include "utils/builtins.h"
+ #include "utils/lsyscache.h"
+ #include "utils/memutils.h"
+ #include "utils/syscache.h"
+ #include "utils/tuplestore.h"
+ #include "utils/datum.h"
+
+ typedef struct WindowStatePerAggData
+ {
+ /* number of input arguments for aggregate */
+ int numArguments;
+
+ /* Oids of transfer functions */
+ Oid transfn_oid;
+ Oid finalfn_oid; /* may be InvalidOid */
+
+ /*
+ * fmgr lookup data for transfer functions --- only valid when
+ * corresponding oid is not InvalidOid. Note in particular that fn_strict
+ * flags are kept here.
+ */
+ FmgrInfo transfn;
+ FmgrInfo finalfn;
+
+ /*
+ * initial value from pg_aggregate entry
+ */
+ Datum initValue;
+ bool initValueIsNull;
+
+ /*
+ * cached value for non-moving frame
+ */
+ Datum resultValue;
+ bool resultValueIsNull;
+ bool hasResult;
+
+ /*
+ * We need the len and byval info for the agg's input, result, and
+ * transition data types in order to know how to copy/delete values.
+ */
+ int16 inputtypeLen,
+ resulttypeLen,
+ transtypeLen;
+ bool inputtypeByVal,
+ resulttypeByVal,
+ transtypeByVal;
+
+ /* point to perfuncstate */
+ int funcno;
+ } WindowStatePerAggData;
+
+ typedef struct WindowStatePerGroupData
+ {
+ Datum transValue; /* current transition value */
+ bool transValueIsNull;
+
+ bool noTransValue; /* true if transValue not set yet */
+ bool doneResult; /* true if cached result has been returned */
+ } WindowStatePerGroupData;
+
+ typedef struct WindowStatePerFuncData
+ {
+ /* Links to WFunc expr and state nodes this working state is for */
+ WFuncExprState *wfuncstate;
+ WFunc *wfunc;
+
+ /* number of input arguments for aggregate */
+ int numArguments;
+
+ /*
+ * fmgr lookup data for transfer functions --- only valid when
+ * corresponding oid is not InvalidOid. Note in particular that fn_strict
+ * flags are kept here.
+ */
+ FmgrInfo flinfo;
+
+ /*
+ * We need the len and byval info for the result of each function
+ * in order to know how to copy/delete values.
+ */
+ int16 resulttypeLen;
+ bool resulttypeByVal;
+
+ /* not window supported (normal aggregate) function? */
+ bool pure_agg;
+ int aggno;
+ } WindowStatePerFuncData;
+
+ /*
+ * WindowObject is the core data that represents the window.
+ * The window may have frame and partition but not always, it depends
+ * on the Buffering Strategy. All the window function APIs are
+ * called with this object.
+ */
+ typedef struct WindowObjectData
+ {
+ WindowState *winstate; /* parent WindowState */
+ ExprContext *econtext; /* window expression context as like window node */
+ Tuplestorestate *buffer; /* rows storage */
+ int strategy; /* buffering strategy */
+ HeapTuple currentrow; /* actual data of the current row */
+
+ /*
+ * currentptr is actually pointing the next row to the current.
+ */
+ int currentptr;
+
+ /*
+ * while iterator is executing, any seeking operation is forbidden, since
+ * iterator omits its seeking by seq scanning buffer without resetting
+ * buffer read pointers.
+ */
+ bool iterating;
+
+ /*
+ * frame informations
+ */
+ int64 f_currentpos; /* relative position of the current row in the frame */
+ int f_headptr; /* read pointer of the head row */
+ int f_tailptr; /* read pointer of the tail row */
+ int64 f_rownum; /* total row number of the frame */
+ int f_shrinking; /* frame's shrinking row number until the next frame */
+ bool f_shrinked; /* frame was shrinked since the last time */
+ int f_extended; /* frame's extended row number since the last time */
+
+ int64 p_currentpos; /* relative position of the current row in the partition */
+ int p_headptr; /* read pointer of the head row */
+ int p_tailptr; /* read pointer of the tail row */
+ int64 p_rownum; /* total row number of the frame */
+ } WindowObjectData;
+
+ /*
+ * WindowIter is an iterator to scan rows in the frame or
+ * the partition. Since WinFrameGetArg/WinPartGetArg or etc.
+ * is too heavy to call many times, iterator makes it easy.
+ * During the iterator scans rows, WindowObject related to
+ * this iterator is locked and cannot seek by itself. First
+ * finish the iterator scan then WindowObject can seek rows again.
+ */
+ typedef struct WindowIterData
+ {
+ WindowObject winobj; /* the frame which this itrator came from */
+ int type; /* FRAME or PARTITION */
+ int position; /* current position within the window */
+ bool finished; /* has finished? */
+ } WindowIterData;
+
+ #define WINDOW_CHECK_STRATEGY(winobj, req) do{\
+ if ((winobj)->strategy < (req))\
+ elog(ERROR, "window function API violation");\
+ } while(0)
+
+ #define WINDOW_TYPE_ROW 1
+ #define WINDOW_TYPE_FRAME 2
+ #define WINDOW_TYPE_PARTITION 3
+
+ static void initialize_windowaggregate(WindowState *winstate,
+ WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate,
+ WindowStatePerGroup pergroupstate);
+ static void advance_windowaggregate(WindowState *winstate,
+ WindowIterData *iter, WindowStatePerFunc perfuncstate,
+ WindowStatePerAgg peraggstate, WindowStatePerGroup pergroupstate);
+ static void finalize_windowaggregate(WindowState *winstate,
+ WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate,
+ WindowStatePerGroup pergroupstate, Datum *result, bool *isnull);
+
+ static void eval_windowaggregate(WindowState *winstate, WindowObject winobj);
+ static void eval_windowfunction(WindowState *winstate, WindowObject winobj,
+ WindowStatePerFunc perfuncstate, Datum *result, bool *isnull);
+
+ static WindowObject init_window_object(WindowState *winstate);
+ static void advance_row(WindowState *winstate);
+ static void start_frame(WindowState *winstate);
+ static void finish_frame(WindowState *winstate);
+ static void store_partition(WindowState *winstate);
+ static void release_partition(WindowState *winstate);
+
+ static WindowStatePerAggData *initialize_peragg(WindowState *winstate, WFunc *wfunc,
+ WindowStatePerAgg peraggstate);
+ static bool is_peer(WindowState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2);
+ static bool window_seek(WindowObject winobj, int seek_pos, int seek_type, int window_type);
+
+ /*
+ * initialize_windowaggregate
+ * parallel to initialize_aggregate in nodeAgg.c
+ */
+ static void
+ initialize_windowaggregate(WindowState *winstate,
+ WindowStatePerFunc perfuncstate,
+ WindowStatePerAgg peraggstate,
+ WindowStatePerGroup pergroupstate)
+ {
+ MemoryContext oldContext;
+
+ if (peraggstate->initValueIsNull)
+ pergroupstate->transValue = peraggstate->initValue;
+ else
+ {
+ oldContext = MemoryContextSwitchTo(winstate->wincontext);
+ pergroupstate->transValue = datumCopy(peraggstate->initValue,
+ peraggstate->transtypeByVal,
+ peraggstate->transtypeLen);
+ MemoryContextSwitchTo(oldContext);
+ }
+ pergroupstate->transValueIsNull = peraggstate->initValueIsNull;
+ pergroupstate->noTransValue = peraggstate->initValueIsNull;
+ }
+
+ /*
+ * advance_windowaggregate
+ * parallel to advance_aggregate in nodeAgg.c
+ *
+ * Contrast to nodeAgg.c, arguments of the function are all ExprState
+ * instead of Datum itself. We convert it to Datum with the current row
+ * to match trans function compatibility.
+ */
+ static void
+ advance_windowaggregate(WindowState *winstate,
+ WindowIterData *iter,
+ WindowStatePerFunc perfuncstate,
+ WindowStatePerAgg peraggstate,
+ WindowStatePerGroup pergroupstate)
+ {
+ WFuncExprState *wfuncstate = perfuncstate->wfuncstate;
+ int numArguments = perfuncstate->numArguments;
+ FunctionCallInfoData fcinfodata;
+ FunctionCallInfo fcinfo = &fcinfodata;
+ Datum newVal;
+ ListCell *arg;
+ int i;
+ MemoryContext oldContext;
+
+ /* We start from 1, since the 0th arg will be the transition value */
+ i = 1;
+ foreach(arg, wfuncstate->args)
+ {
+ ExprState *argstate = (ExprState *) lfirst(arg);
+ bool isnull;
+
+ /*
+ * we assume the argument expressions are always static nodes.
+ */
+ Assert(IsA(argstate->expr, Var) || IsA(argstate->expr, Const));
+ fcinfo->arg[i] = WinIterGetArg(iter, argstate, &isnull);
+ fcinfo->argnull[i] = isnull;
+ i++;
+ }
+
+ if (peraggstate->transfn.fn_strict)
+ {
+ /*
+ * For a strict transfn, nothing happens when there's a NULL input; we
+ * just keep the prior transValue.
+ */
+ for(i = 1; i <= numArguments; i++)
+ {
+ if (fcinfo->argnull[i])
+ return;
+ }
+ if (pergroupstate->noTransValue)
+ {
+ /*
+ * transValue has not been initialized. This is the first non-NULL
+ * input value. We use it as the initial value for transValue. (We
+ * already checked that the agg's input type is binary-compatible
+ * with its transtype, so straight copy here is OK.)
+ *
+ * We must copy the datum into aggcontext if it is pass-by-ref. We
+ * do not need to pfree the old transValue, since it's NULL.
+ */
+ oldContext = MemoryContextSwitchTo(winstate->wincontext);
+ pergroupstate->transValue = datumCopy(fcinfo->arg[1],
+ peraggstate->transtypeByVal,
+ peraggstate->transtypeLen);
+ pergroupstate->transValueIsNull = false;
+ pergroupstate->noTransValue = false;
+ MemoryContextSwitchTo(oldContext);
+ return;
+ }
+ if (pergroupstate->transValueIsNull)
+ {
+ /*
+ * Don't call a strict function with NULL inputs. Note it is
+ * possible to get here despite the above tests, if the transfn is
+ * strict *and* returned a NULL on a prior cycle. If that happens
+ * we will propagate the NULL all the way to the end.
+ */
+ return;
+ }
+ }
+
+ oldContext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_tuple_memory);
+
+ /*
+ * OK to call the transition function
+ */
+ InitFunctionCallInfoData(*fcinfo, &(peraggstate->transfn),
+ numArguments + 1,
+ (void *) winstate, NULL);
+ fcinfo->arg[0] = pergroupstate->transValue;
+ fcinfo->argnull[0] = pergroupstate->transValueIsNull;
+ newVal = FunctionCallInvoke(fcinfo);
+
+ /*
+ * If pass-by-ref datatype, must copy the new value into aggcontext and
+ * pfree the prior transValue. But if transfn returned a pointer to its
+ * first input, we don't need to do anything.
+ */
+ if (!peraggstate->transtypeByVal &&
+ DatumGetPointer(newVal) != DatumGetPointer(pergroupstate->transValue))
+ {
+ if (!fcinfo->isnull)
+ {
+ MemoryContextSwitchTo(winstate->wincontext);
+ newVal = datumCopy(newVal,
+ peraggstate->transtypeByVal,
+ peraggstate->transtypeLen);
+ }
+ if (!pergroupstate->transValueIsNull)
+ pfree(DatumGetPointer(pergroupstate->transValue));
+ }
+
+ MemoryContextSwitchTo(oldContext);
+ pergroupstate->transValue = newVal;
+ pergroupstate->transValueIsNull = fcinfo->isnull;
+ }
+
+ /*
+ * finalize_windowaggregate
+ * parallel to finalize_aggregate in nodeAgg.c
+ */
+ static void
+ finalize_windowaggregate(WindowState *winstate,
+ WindowStatePerFunc perfuncstate,
+ WindowStatePerAgg peraggstate,
+ WindowStatePerGroup pergroupstate,
+ Datum *result, bool *isnull)
+ {
+ MemoryContext oldContext;
+
+ oldContext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_tuple_memory);
+
+ /*
+ * Apply the agg's finalfn if one is provided, else return transValue.
+ */
+ if (OidIsValid(peraggstate->finalfn_oid))
+ {
+ FunctionCallInfoData fcinfo;
+
+ InitFunctionCallInfoData(fcinfo, &(peraggstate->finalfn), 1,
+ (void *) winstate, NULL);
+ fcinfo.arg[0] = pergroupstate->transValue;
+ fcinfo.argnull[0] = pergroupstate->transValueIsNull;
+ if (fcinfo.flinfo->fn_strict && pergroupstate->transValueIsNull)
+ {
+ /* don't call a strict function with NULL inputs */
+ *result = (Datum) 0;
+ *isnull = true;
+ }
+ else
+ {
+ *result = FunctionCallInvoke(&fcinfo);
+ *isnull = fcinfo.isnull;
+ }
+ }
+ else
+ {
+ *result = pergroupstate->transValue;
+ *isnull = pergroupstate->transValueIsNull;
+ }
+
+ /*
+ * If result is pass-by-ref, make sure it is in the right context.
+ */
+ if (!peraggstate->resulttypeByVal && !*isnull &&
+ !MemoryContextContains(CurrentMemoryContext,
+ DatumGetPointer(*result)))
+ *result = datumCopy(*result,
+ peraggstate->resulttypeByVal,
+ peraggstate->resulttypeLen);
+ MemoryContextSwitchTo(oldContext);
+
+ }
+
+ /*
+ * eval_windowaggregate
+ * evaluate normal aggregates (proiswfunc is false but proisagg is true).
+ *
+ * Many flows and ideas are ported from nodeAgg.c.
+ *
+ * If a window frame is moving whole the calculation of trans/final
+ * functions are executed again, whereas if not moving the only result
+ * is cached and returned while the frame is valid.
+ */
+ static void
+ eval_windowaggregate(WindowState *winstate, WindowObject winobj)
+ {
+ WindowStatePerAgg peraggstate;
+ WindowStatePerGroup pergroupstate;
+ WindowIter iter;
+ int funcno, numaggs;
+ int i;
+ MemoryContext oldContext;
+ ExprContext *econtext;
+ bool need_scan;
+ Datum *result;
+ bool *isnull;
+
+ numaggs = winstate->numaggs;
+ /*
+ * nothing to do.
+ */
+ if(numaggs == 0)
+ return;
+
+ /* final output execution is on ps_ExprContext */
+ econtext = winstate->ss.ps.ps_ExprContext;
+
+ need_scan = true;
+ for(i = 0; i < numaggs; i++)
+ {
+ peraggstate = &winstate->peragg[i];
+ pergroupstate = &winstate->pergroup[i];
+ pergroupstate->doneResult = false;
+
+ funcno = peraggstate->funcno;
+ result = &econtext->ecxt_aggvalues[funcno];
+ isnull = &econtext->ecxt_aggnulls[funcno];
+
+ if (!WinFrameShrinked(winobj) && !WinFrameExtended(winobj) &&
+ peraggstate->hasResult)
+ {
+ pergroupstate->doneResult = true;
+ /* return the same value as the previous result */
+ *isnull = peraggstate->resultValueIsNull;
+ if (*isnull)
+ continue;
+
+ if (!peraggstate->resulttypeByVal &&
+ !peraggstate->resultValueIsNull &&
+ DatumGetPointer(peraggstate->resultValue) != NULL)
+ {
+ oldContext = MemoryContextSwitchTo(winstate->wincontext);
+ *result = datumCopy(peraggstate->resultValue,
+ peraggstate->resulttypeByVal,
+ peraggstate->resulttypeLen);
+ MemoryContextSwitchTo(oldContext);
+ }
+ else
+ *result = peraggstate->resultValue;
+
+ continue;
+ }
+ else if (WinFrameShrinked(winobj) || !peraggstate->hasResult)
+ {
+ initialize_windowaggregate(winstate,
+ &winstate->perfunc[funcno],
+ &winstate->peragg[i],
+ &winstate->pergroup[i]);
+ }
+ /*
+ * If at least one aggregate needs scan, we go through scan process.
+ */
+ need_scan = true;
+ }
+
+ /*
+ * return if all aggs return cached value.
+ */
+ if (!need_scan)
+ return;
+
+ /*
+ * Scan frame from the head if shrinked.
+ * Otherwise, scan only extended rows.
+ */
+ iter = WinFrameStartIter(winobj,
+ WinFrameShrinked(winobj) ? 0 :
+ WinFrameGetRowNum(winobj) - WinFrameExtendedNum(winobj));
+ while(WinIterNext(iter))
+ {
+ for(i = 0; i < numaggs; i++)
+ {
+ if (winstate->pergroup[i].doneResult)
+ continue;
+ funcno = winstate->peragg[i].funcno;
+ advance_windowaggregate(winstate,
+ iter,
+ &winstate->perfunc[funcno],
+ &winstate->peragg[i],
+ &winstate->pergroup[i]);
+ }
+ }
+ WinIterFinish(iter);
+
+ /*
+ * finalize aggregates and fill result/isnull fields.
+ */
+ for(i = 0; i < numaggs; i++)
+ {
+ peraggstate = &winstate->peragg[i];
+ pergroupstate = &winstate->pergroup[i];
+
+ if (pergroupstate->doneResult)
+ continue;
+ funcno = peraggstate->funcno;
+ result = &econtext->ecxt_aggvalues[funcno];
+ isnull = &econtext->ecxt_aggnulls[funcno];
+ finalize_windowaggregate(winstate,
+ &winstate->perfunc[funcno],
+ peraggstate, pergroupstate,
+ result, isnull);
+
+ /*
+ * If the frame is shrinking, we must re-compute
+ * from the start so cannot reuse the result.
+ */
+ if (WinFrameShrinkingNum(winobj) > 0)
+ {
+ peraggstate->hasResult = false;
+ continue;
+ }
+
+ /*
+ * save the result for the next (non-shrinking frame) call.
+ */
+ if (!peraggstate->resulttypeByVal && !*isnull)
+ {
+ /*
+ * clear old resultValue in order not to leak memory.
+ */
+ if (peraggstate->hasResult &&
+ (DatumGetPointer(peraggstate->resultValue) !=
+ DatumGetPointer(*result)) &&
+ !peraggstate->resultValueIsNull)
+ pfree(DatumGetPointer(peraggstate->resultValue));
+
+ /*
+ * If pass-by-ref, copy it into our global context.
+ */
+ oldContext = MemoryContextSwitchTo(winstate->wincontext);
+ peraggstate->resultValue = datumCopy(*result,
+ peraggstate->resulttypeByVal,
+ peraggstate->resulttypeLen);
+ MemoryContextSwitchTo(oldContext);
+ }
+ else
+ {
+ peraggstate->resultValue = *result;
+ }
+ peraggstate->resultValueIsNull = *isnull;
+ peraggstate->hasResult = true;
+ }
+ }
+
+ /*
+ * eval_windowfunction
+ *
+ * Arguments of window functions are not actual datum but expression node.
+ * This is based on the fact they can access arbitrary row column specified
+ * by their arguments. The window API can handle separate row evaluations.
+ * Since window functions' arguments must be Var or Const by the planner,
+ * fetching arbitrary separate row is always successful.
+ */
+ static void
+ eval_windowfunction(WindowState *winstate, WindowObject winobj,
+ WindowStatePerFunc perfuncstate, Datum *result, bool *isnull)
+ {
+ WFuncExprState *wfuncstate = perfuncstate->wfuncstate;
+ FunctionCallInfoData fcinfo;
+ int i;
+ ListCell *arg;
+ MemoryContext oldContext;
+
+ oldContext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_tuple_memory);
+ InitFunctionCallInfoData(fcinfo, &(perfuncstate->flinfo),
+ perfuncstate->numArguments,
+ (void *) winstate, NULL);
+
+ i = 0;
+ foreach(arg, wfuncstate->args)
+ {
+ ExprState *argstate = (ExprState *) lfirst(arg);
+
+ /*
+ * Window functions' arguments should be Var or Const.
+ * Any other types operation must have done at the outer
+ * nodes.
+ */
+ Assert(IsA(argstate->expr, Var) || IsA(argstate->expr, Const));
+ fcinfo.arg[i] = PointerGetDatum(argstate);
+ i++;
+ }
+
+ *result = FunctionCallInvoke(&fcinfo);
+ *isnull = fcinfo.isnull;
+
+ /*
+ * make sure the pass-by-ref datum is allocated in the appropriate context.
+ */
+ if (!perfuncstate->resulttypeByVal && !fcinfo.isnull &&
+ !MemoryContextContains(CurrentMemoryContext,
+ DatumGetPointer(*result)))
+ *result = datumCopy(*result,
+ perfuncstate->resulttypeByVal,
+ perfuncstate->resulttypeLen);
+
+ MemoryContextSwitchTo(oldContext);
+ }
+
+ /*
+ * init_window_object
+ * initialize WindowObject for each partition. This handles
+ * only core preparation that doesn't depend on the different
+ * buffering strategies.
+ */
+ static WindowObject
+ init_window_object(WindowState *winstate)
+ {
+ WindowObject winobj = winstate->winobj;
+
+ MemSet(winobj, 0, sizeof(WindowObjectData));
+
+ winobj->winstate = winstate;
+ /*
+ * window's econtext is tmpcontext.
+ */
+ winobj->econtext = winstate->tmpcontext;
+
+ winobj->strategy = winstate->strategy;
+
+ /*
+ * set up positions
+ */
+ winobj->f_currentpos = -1;
+ winobj->p_currentpos = -1;
+ winobj->iterating = false;
+
+ return winobj;
+ }
+
+ /*
+ * advance_row
+ * used with WINDOW_BUFFER_ROW.
+ */
+ static void
+ advance_row(WindowState *winstate)
+ {
+ WindowObject winobj = winstate->winobj;
+ Window *node = (Window *) winstate->ss.ps.plan;
+ PlanState *outerPlan;
+ ExprContext *econtext;
+ TupleTableSlot *outerslot;
+ TupleTableSlot *firstSlot;
+
+ outerPlan = outerPlanState(winstate);
+ econtext = winstate->ss.ps.ps_ExprContext;
+ firstSlot = winstate->ss.ss_ScanTupleSlot;
+
+ outerslot = ExecProcNode(outerPlan);
+ if (!TupIsNull(outerslot))
+ {
+ if (winstate->prt_firstTuple == NULL)
+ {
+ /*
+ * the first row of the first partition
+ */
+ winstate->prt_firstTuple = ExecCopySlotTuple(outerslot);
+ winobj = init_window_object(winstate);
+ }
+ else
+ {
+ /*
+ * shouldFree is false, since
+ * prt_firstTuple is reused again and again.
+ */
+ ExecStoreTuple(winstate->prt_firstTuple,
+ firstSlot,
+ InvalidBuffer,
+ false);
+ if (!execTuplesMatch(firstSlot,
+ outerslot,
+ node->prtNumCols, node->prtColIdx,
+ winstate->prtEqfunctions,
+ econtext->ecxt_per_tuple_memory))
+ {
+ /*
+ * We free prt_firstTuple here. And it means
+ * end of the partition, we clear partition-based
+ * information such like perfunc->flinfo.fn_extra
+ */
+ heap_freetuple(winstate->prt_firstTuple);
+ winstate->prt_firstTuple = ExecCopySlotTuple(outerslot);
+ release_partition(winstate);
+ winobj = init_window_object(winstate);
+ }
+ }
+ /*
+ * We must have currentrow, for process_current needs it.
+ * also, p_currentpos is used in WinRowXXX APIs.
+ */
+ winobj->currentrow = ExecCopySlotTuple(outerslot);
+ winobj->p_currentpos++;
+ }
+ else
+ {
+ /*
+ * all rows are processed. let's finish it.
+ */
+ release_partition(winstate);
+ winstate->win_done = true;
+ return;
+ }
+ }
+
+ /*
+ * start_frame
+ */
+ static void
+ start_frame(WindowState *winstate)
+ {
+ WindowObject winobj = winstate->winobj;
+ Window *node = (Window *) winstate->ss.ps.plan;
+ Tuplestorestate *buffer = winobj->buffer;
+ TupleTableSlot *slot = winobj->econtext->ecxt_outertuple;
+ TupleTableSlot *tmpslot = winstate->ss.ss_ScanTupleSlot;
+ int f_shrinking, f_extended;
+
+ if (!winobj->f_headptr)
+ {
+ /*
+ * first row
+ */
+ winobj->f_headptr = tuplestore_alloc_read_pointer(buffer, winstate->eflags);
+ switch(node->preceding_type)
+ {
+ case FRAME_UNBOUNDED:
+ f_shrinking = 0;
+ break;
+ case FRAME_CURRENT_ROWS:
+ f_shrinking = 1;
+ break;
+ case FRAME_CURRENT_RANGE:
+ /* UNSUPPORTED */
+ elog(ERROR, "unknown preceding type %d", node->preceding_type);
+ return; /* keep compiler quiet */
+ case FRAME_VALUE_ROWS:
+ if (node->preceding_rows > 0)
+ f_shrinking = 0;
+ else
+ f_shrinking = 1;
+ break;
+ case FRAME_VALUE_RANGE:
+ /* UNSUPPORTED */
+ default:
+ elog(ERROR, "unknown preceding type %d", node->preceding_type);
+ return; /* keep compiler quiet */
+ }
+
+ Assert(!winobj->f_tailptr);
+ winobj->f_tailptr = tuplestore_alloc_read_pointer(buffer, winstate->eflags);
+ switch(node->following_type)
+ {
+ case FRAME_UNBOUNDED:
+ f_extended = winobj->p_rownum;
+ tuplestore_copy_read_pointer(buffer, winobj->p_tailptr, winobj->f_tailptr);
+ break;
+ case FRAME_CURRENT_ROWS:
+ f_extended = 1;
+ /* f_tailptr == currentptr */
+ break;
+ case FRAME_CURRENT_RANGE:
+ f_extended = 1;
+ /*
+ * read the current row but do not save the pointer,
+ * for the actual reading is at the end of the function.
+ */
+ tuplestore_copy_read_pointer(buffer, winobj->currentptr, 0);
+ tuplestore_gettupleslot(buffer, true, slot);
+ while(true)
+ {
+ if (!tuplestore_gettupleslot(buffer, true, tmpslot))
+ {
+ /*
+ * no more rows.
+ * remove the eof flag.
+ */
+ if (tuplestore_ateof(buffer))
+ tuplestore_advance(buffer, false);
+ break;
+ }
+
+ if (!is_peer(winstate, slot, tmpslot))
+ {
+ /*
+ * tried the next row but failed,
+ * so go back to the previous.
+ */
+ tuplestore_advance(buffer, false);
+ break;
+ }
+ f_extended++;
+ }
+ tuplestore_advance(buffer, false);
+ tuplestore_copy_read_pointer(buffer, 0, winobj->f_tailptr);
+ break;
+ case FRAME_VALUE_ROWS:
+ {
+ int i;
+
+ if (winobj->p_rownum < node->following_rows)
+ f_extended = winobj->p_rownum;
+ else
+ f_extended = node->following_rows;
+ for(i = 0; i < f_extended; i++)
+ tuplestore_advance(buffer, true);
+ tuplestore_copy_read_pointer(buffer, 0, winobj->f_tailptr);
+ }
+ break;
+ case FRAME_VALUE_RANGE:
+ /* UNSUPPORTED */
+ default:
+ elog(ERROR, "unknown following type %d", node->following_type);
+ return; /* keep compiler quiet */
+ }
+ winobj->f_shrinking = f_shrinking;
+ winobj->f_extended = f_extended;
+ /*
+ * In the first row, rownum of frame = extended rownum of frame.
+ */
+ winobj->f_rownum = f_extended;
+ }
+ else
+ {
+ /* not first */
+ switch(node->preceding_type)
+ {
+ case FRAME_UNBOUNDED:
+ /* never shinks */
+ f_shrinking = 0;
+ break;
+ case FRAME_CURRENT_ROWS:
+ /* advance one row */
+ f_shrinking = 1;
+ /* f_headptr will be updated in finish_frame() */
+ break;
+ case FRAME_CURRENT_RANGE:
+ /* UNSUPPORTED */
+ elog(ERROR, "unknown preceding type %d", node->preceding_type);
+ return; /* keep compiler quiet */
+ case FRAME_VALUE_ROWS:
+ if (node->preceding_rows <= winobj->p_currentpos + 1)
+ f_shrinking = 1;
+ else
+ f_shrinking = 0;
+ /* f_headptr will be updated in finish_frame() */
+ break;
+ case FRAME_VALUE_RANGE:
+ /* UNSUPPORTED */
+ default:
+ elog(ERROR, "unknown preceding type %d", node->preceding_type);
+ return; /* keep compiler quiet */
+ }
+ winobj->f_shrinking = f_shrinking;
+
+ switch(node->following_type)
+ {
+ case FRAME_UNBOUNDED:
+ /* never extends */
+ f_extended = 0;
+ break;
+ case FRAME_CURRENT_ROWS:
+ /* advance one row */
+ f_extended = 1;
+ tuplestore_copy_read_pointer(buffer, winobj->currentptr, winobj->f_tailptr);
+ break;
+ case FRAME_CURRENT_RANGE:
+ ExecStoreTuple(winobj->currentrow,
+ tmpslot, InvalidBuffer, false);
+ tuplestore_copy_read_pointer(buffer, winobj->currentptr, 0);
+ tuplestore_gettupleslot(buffer, true, slot);
+ if (!is_peer(winstate, tmpslot, slot))
+ {
+ f_extended = 1;
+ while(true)
+ {
+ if (!tuplestore_gettupleslot(buffer, true, tmpslot))
+ {
+ /*
+ * no more rows.
+ * remove the eof flag.
+ */
+ if (tuplestore_ateof(buffer))
+ tuplestore_advance(buffer, false);
+ break;
+ }
+
+ if (!is_peer(winstate, slot, tmpslot))
+ {
+ /*
+ * tried the next row but failed,
+ * so go back to the previous.
+ */
+ tuplestore_advance(buffer, false);
+ break;
+ }
+ f_extended++;
+ }
+ tuplestore_advance(buffer, false);
+ tuplestore_copy_read_pointer(buffer, 0, winobj->f_tailptr);
+ }
+ else
+ {
+ /*
+ * the frame doesn't extend, which means
+ * the tail pointer stays where it is.
+ */
+ f_extended = 0;
+ }
+ break;
+ case FRAME_VALUE_ROWS:
+ if (node->following_rows + winobj->p_currentpos < winobj->p_rownum)
+ f_extended = 1;
+ else
+ f_extended = 0;
+
+ if (f_extended > 0)
+ {
+ /* update f_tailptr */
+ tuplestore_copy_read_pointer(buffer, winobj->f_tailptr, 0);
+ tuplestore_advance(buffer, true);
+ tuplestore_copy_read_pointer(buffer, 0, winobj->f_tailptr);
+ }
+ break;
+ case FRAME_VALUE_RANGE:
+ /* UNSUPPORTED */
+ default:
+ elog(ERROR, "unknown following type %d", node->following_type);
+ return; /* keep compiler quiet */
+ }
+ winobj->f_extended = f_extended;
+ winobj->f_rownum += f_extended;
+
+ heap_freetuple(winobj->currentrow);
+ }
+
+ /*
+ * advance current row
+ */
+ tuplestore_copy_read_pointer(buffer, winobj->currentptr, 0);
+ tuplestore_gettupleslot(buffer, true, slot);
+ tuplestore_copy_read_pointer(buffer, 0, winobj->currentptr);
+ winobj->f_currentpos++;
+ winobj->p_currentpos++;
+ winobj->currentrow = ExecCopySlotTuple(slot);
+ }
+
+ /*
+ * finish_frame
+ */
+ static void
+ finish_frame(WindowState *winstate)
+ {
+ WindowObject winobj = winstate->winobj;
+ Tuplestorestate *buffer = winobj->buffer;
+ int i, f_shrinking = winobj->f_shrinking;
+
+ if (f_shrinking > 0)
+ {
+ tuplestore_copy_read_pointer(buffer, winobj->f_headptr, 0);
+ for(i = 0; i < f_shrinking; i++)
+ tuplestore_advance(buffer, true);
+ tuplestore_copy_read_pointer(buffer, 0, winobj->f_headptr);
+ /*
+ * In the next frame, WinFrameShrinked(winobj) = true
+ */
+ winobj->f_shrinked = true;
+ winobj->f_rownum -= f_shrinking;
+ }
+ else
+ {
+ winobj->f_shrinked = false;
+ }
+ }
+
+ /*
+ * store_partition
+ * buffer all rows contained in the current partition.
+ */
+ static void
+ store_partition(WindowState *winstate)
+ {
+ Window *node = (Window *) winstate->ss.ps.plan;
+ PlanState *outerPlan;
+ ExprContext *econtext;
+ TupleTableSlot *outerslot;
+ TupleTableSlot *firstSlot;
+ Tuplestorestate *buffer;
+ WindowObject winobj;
+
+ outerPlan = outerPlanState(winstate);
+ econtext = winstate->ss.ps.ps_ExprContext;
+ firstSlot = winstate->ss.ss_ScanTupleSlot;
+ winobj = init_window_object(winstate);
+
+ /*
+ * tuplestore needs randomAccess
+ */
+ buffer = tuplestore_begin_heap(true, false, work_mem);
+
+ /*
+ * allocate CURRENT ROW, head and tail pointers of the partition
+ */
+ winobj->currentptr = tuplestore_alloc_read_pointer(buffer, winstate->eflags);
+ winobj->p_headptr = tuplestore_alloc_read_pointer(buffer, winstate->eflags);
+ winobj->p_tailptr = tuplestore_alloc_read_pointer(buffer, winstate->eflags);
+ winobj->buffer = buffer;
+
+ /*
+ * see if the partition is the first one?
+ */
+ if (winstate->prt_firstTuple == NULL)
+ {
+ outerslot = ExecProcNode(outerPlan);
+ if (!TupIsNull(outerslot))
+ {
+ winstate->prt_firstTuple = ExecCopySlotTuple(outerslot);
+ }
+ else
+ {
+ /* nothing will be returned */
+ winstate->win_done = true;
+ finish_frame(winstate);
+ return;
+ }
+ }
+
+ if (winstate->prt_firstTuple != NULL)
+ {
+ ExecStoreTuple(winstate->prt_firstTuple,
+ firstSlot,
+ InvalidBuffer,
+ true);
+ winstate->prt_firstTuple = NULL;
+ outerslot = firstSlot;
+
+ /*
+ * store partition rows into window buffer until
+ * the bottom of the partition.
+ */
+ for(;;)
+ {
+ tuplestore_puttupleslot(buffer, outerslot);
+ winobj->p_rownum++;
+
+ outerslot = ExecProcNode(outerPlan);
+ if (TupIsNull(outerslot))
+ {
+ /*
+ * hit the bottom of the last partition.
+ */
+ winstate->win_done = true;
+ break;
+ }
+
+ if (!execTuplesMatch(firstSlot,
+ outerslot,
+ node->prtNumCols, node->prtColIdx,
+ winstate->prtEqfunctions,
+ econtext->ecxt_per_tuple_memory))
+ {
+ /*
+ * at the end of each partition
+ * copy the tuple for the next partition cycle.
+ */
+ winstate->prt_firstTuple = ExecCopySlotTuple(outerslot);
+ break;
+ }
+ }
+ }
+
+ /*
+ * write pointer - 1 row is the last row of the partition.
+ */
+ tuplestore_write_to_read_pointer(buffer, winobj->p_tailptr);
+ tuplestore_select_read_pointer(buffer, winobj->p_tailptr);
+ tuplestore_advance(buffer, false);
+ tuplestore_select_read_pointer(buffer, 0);
+
+ winstate->prt_processing = true;
+ }
+
+ /*
+ * release_partition
+ * clear information kept within a partition, including
+ * funcstate/fn_extra, tuplestore and aggregate result.
+ */
+ static void
+ release_partition(WindowState *winstate)
+ {
+ WindowObject winobj = winstate->winobj;
+ int i;
+ int numfuncs = winstate->numfuncs;
+
+ for(i = 0; i < numfuncs; i++)
+ {
+ WindowStatePerFunc perfuncstate = &(winstate->perfunc[i]);
+
+ if (perfuncstate->flinfo.fn_extra != NULL)
+ {
+ pfree(perfuncstate->flinfo.fn_extra);
+ /*
+ * Be sure to set NULL, which is one of the signs
+ * that the partition is brand new.
+ */
+ perfuncstate->flinfo.fn_extra = NULL;
+ }
+
+ /*
+ * reset agg result cache
+ */
+ if (perfuncstate->pure_agg)
+ {
+ int aggno = perfuncstate->aggno;
+ WindowStatePerAggData *peraggstate = &winstate->peragg[aggno];
+
+ if (!peraggstate->resulttypeByVal &&
+ peraggstate->hasResult &&
+ !peraggstate->resultValueIsNull)
+ {
+ pfree(DatumGetPointer(peraggstate->resultValue));
+ peraggstate->resultValueIsNull = true;
+ }
+ peraggstate->hasResult = false;
+ }
+ }
+
+ if(winobj->buffer)
+ tuplestore_end(winobj->buffer);
+ winstate->prt_processing = false;
+ }
+
+ /*
+ * process_current
+ * given frame, evaluate each window function with it
+ * and return the result tuple.
+ */
+ static TupleTableSlot *
+ process_current(WindowState *winstate, WindowObject winobj)
+ {
+ ExprContext *econtext;
+ ProjectionInfo *projInfo;
+ int i;
+ int numfuncs;
+
+ /* final output execution is on ps_ExprContext */
+ econtext = winstate->ss.ps.ps_ExprContext;
+ numfuncs = winstate->numfuncs;
+
+ /*
+ * Clear the per-output-tuple context for current row
+ */
+ ResetExprContext(econtext);
+
+ for(i = 0; i < numfuncs; i++)
+ {
+ WindowStatePerFunc perfuncstate;
+ Datum *result;
+ bool *isnull;
+
+ perfuncstate = &(winstate->perfunc[i]);
+ /*
+ * normal aggregates are called from specialized environment
+ * rather than as window function.
+ * aggregates are called in a sequence later for performance,
+ * so we skip them here.
+ */
+ if (perfuncstate->pure_agg)
+ continue;
+ result = &(econtext->ecxt_aggvalues[i]);
+ isnull = &(econtext->ecxt_aggnulls[i]);
+ eval_windowfunction(winstate, winobj, perfuncstate, result, isnull);
+ }
+
+ /*
+ * process aggregate with trans and final functions, if any.
+ */
+ if (winstate->numaggs > 0)
+ eval_windowaggregate(winstate, winobj);
+
+ /*
+ * read back the current row from the frame to econtext
+ * as an outer tuple. econtext->ecxt_outertuple will be used
+ * in the projection (evaluation of the current row after
+ * window function executions).
+ */
+ projInfo = winstate->ss.ps.ps_ProjInfo;
+ econtext->ecxt_outertuple = winstate->ss.ss_ScanTupleSlot;
+ ExecStoreTuple(winobj->currentrow,
+ econtext->ecxt_outertuple,
+ InvalidBuffer,
+ false);
+ return ExecProject(projInfo, NULL);
+ }
+
+ /* -----------------
+ * ExecWindow
+ *
+ * ExecWindow receives tuples from its outer subplan and
+ * creates or feeds the WindowObject then process window functions
+ * with the WindowObject. This node doesn't reduce nor qualify any row
+ * so the number of returned rows are exactly same as its outer
+ * subplan's result.
+ * The WindowObject works as if some temporary table that stores row values
+ * and provides evaluation functionality, which needs an econtext so that
+ * window functions use it as the core executor does. Thus, we need
+ * two econtext for both of this purpose and the result tuple evaluation purpose.
+ *
+ * Each Window node has their own buffering strategy. We currently 2 types,
+ * BUFFER_ROW and BUFFER_PARTITION. In BUFFER_ROW strategy, no additional rows
+ * after the current row are stored, whereas in BUFFER_PARTITION all the
+ * rows in the partition are stored at the first row in the partition.
+ * -----------------
+ */
+ TupleTableSlot *
+ ExecWindow(WindowState *winstate)
+ {
+ TupleTableSlot *slot;
+
+ if (winstate->win_done && !winstate->prt_processing)
+ return NULL;
+
+ if (winstate->strategy == WINDOW_BUFFER_PARTITION)
+ {
+ if (!winstate->prt_processing)
+ store_partition(winstate);
+
+ /*
+ * we double-check if we can go processing frame.
+ * It means the first partition has no rows
+ * when this second check is false.
+ */
+ if (winstate->win_done && !winstate->prt_processing)
+ return NULL;
+
+ start_frame(winstate);
+ }
+ else
+ {
+ Assert(winstate->strategy == WINDOW_BUFFER_ROW);
+ advance_row(winstate);
+
+ /*
+ * BUFFER_ROW will detect the bottom by calling
+ * advance_row, so if it is stop it here.
+ */
+ if (winstate->win_done)
+ return NULL;
+ }
+
+ /*
+ * This is the actual process to evaluate expressions
+ * and compute the result, then projection is done.
+ * It is the common code among the different strategies.
+ */
+ slot = process_current(winstate, winstate->winobj);
+
+ if (winstate->strategy == WINDOW_BUFFER_PARTITION)
+ {
+ finish_frame(winstate);
+
+ /*
+ * make sure to clear the frame on the end of the partition.
+ */
+ if (winstate->prt_processing &&
+ winstate->winobj->p_currentpos == winstate->winobj->p_rownum - 1)
+ release_partition(winstate);
+ }
+
+ return slot;
+ }
+
+ /* -----------------
+ * ExecInitWindow
+ *
+ * Creates the run-time information for the Window node produced by the
+ * planner and initializes its outer subtree
+ * -----------------
+ */
+ WindowState *
+ ExecInitWindow(Window *node, EState *estate, int eflags)
+ {
+ WindowState *winstate;
+ Plan *outerPlan;
+ ExprContext *econtext;
+ ExprContext *tmpcontext;
+ WindowObject winobj;
+ WindowStatePerFunc perfunc;
+ WindowStatePerAgg peragg;
+ WindowStatePerGroup pergroup;
+ int numfuncs = 0, funcno,
+ numaggs = 0, aggno;
+ int strategy;
+ ListCell *l;
+
+ /* check for unsupported flags */
+ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK)));
+
+ winstate = makeNode(WindowState);
+ winstate->ss.ps.plan = (Plan *) node;
+ winstate->ss.ps.state = estate;
+ winstate->eflags = (EXEC_FLAG_REWIND | EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK);
+
+ /*
+ * Create expression contexts. We need two, one for per-input-tuple
+ * processing and one for per-output-tuple processing. We cheat a little
+ * by using ExecAssignExprContext() to build both.
+ */
+ ExecAssignExprContext(estate, &winstate->ss.ps);
+ tmpcontext = winstate->ss.ps.ps_ExprContext;
+ winstate->tmpcontext = tmpcontext;
+ ExecAssignExprContext(estate, &winstate->ss.ps);
+
+ winstate->wincontext =
+ AllocSetContextCreate(CurrentMemoryContext,
+ "WinContext",
+ ALLOCSET_DEFAULT_MINSIZE,
+ ALLOCSET_DEFAULT_INITSIZE,
+ ALLOCSET_DEFAULT_MAXSIZE);
+
+ #define WINDOW_NSLOTS 3
+
+ /*
+ * tuple table initialization
+ */
+ ExecInitScanTupleSlot(estate, &winstate->ss);
+ ExecInitResultTupleSlot(estate, &winstate->ss.ps);
+
+ /*
+ * This slot is used as the frame current row, and
+ * some temporary row in window functions.
+ */
+ tmpcontext->ecxt_outertuple = ExecInitExtraTupleSlot(estate);
+
+ winstate->ss.ps.targetlist = (List *)
+ ExecInitExpr((Expr *) node->plan.targetlist,
+ (PlanState *) winstate);
+ winstate->ss.ps.qual = NIL;
+
+ /*
+ * initialize child nodes
+ *
+ * We shield the child node from the need to support REWIND, BACKWARD, or
+ * MARK/RESTORE.
+ */
+ eflags &= ~(EXEC_FLAG_REWIND | EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK);
+ outerPlan = outerPlan(node);
+ outerPlanState(winstate) = ExecInitNode(outerPlan, estate, eflags);
+
+ /*
+ * initialize result tuple type and projection info.
+ */
+ ExecAssignScanTypeFromOuterPlan(&winstate->ss);
+
+ /*
+ * initialize result tuple type and projection info.
+ */
+ ExecAssignResultTypeFromTL(&winstate->ss.ps);
+ ExecAssignProjectionInfo(&winstate->ss.ps, NULL);
+ ExecSetSlotDescriptor(tmpcontext->ecxt_outertuple,
+ winstate->ss.ss_ScanTupleSlot->tts_tupleDescriptor);
+ ExecStoreAllNullTuple(tmpcontext->ecxt_outertuple);
+
+ winobj = (WindowObject) palloc0(sizeof(WindowObjectData));
+ winstate->winobj = winobj;
+
+ numfuncs = winstate->numfuncs;
+ numaggs = winstate->numaggs;
+ if (node->prtNumCols > 0)
+ winstate->prtEqfunctions = execTuplesMatchPrepare(node->prtNumCols,
+ node->prtOperators);
+ if (node->ordNumCols > 0)
+ winstate->ordEqfunctions = execTuplesMatchPrepare(node->ordNumCols,
+ node->ordOperators);
+
+ /*
+ * Window functions use aggvalues and aggnulls as well as Agg node.
+ */
+ econtext = winstate->ss.ps.ps_ExprContext;
+ econtext->ecxt_aggvalues = (Datum *) palloc0(sizeof(Datum) * numfuncs);
+ econtext->ecxt_aggnulls = (bool *) palloc0(sizeof(bool) * numfuncs);
+
+ /*
+ * allocate per-wfunc/per-agg state information.
+ */
+ perfunc = (WindowStatePerFunc) palloc0(sizeof(WindowStatePerFuncData) * numfuncs);
+ peragg = (WindowStatePerAgg) palloc0(sizeof(WindowStatePerAggData) * numaggs);
+ pergroup = (WindowStatePerGroup) palloc0(sizeof(WindowStatePerGroupData) * numaggs);
+ winstate->perfunc = perfunc;
+ winstate->peragg = peragg;
+ winstate->pergroup = pergroup;
+
+ winstate->prt_processing = false;
+ winstate->win_done = false;
+
+ strategy = WINDOW_BUFFER_ROW;
+
+ funcno = -1;
+ aggno = -1;
+ foreach(l, winstate->funcs)
+ {
+ WFuncExprState *wfuncstate = (WFuncExprState *) lfirst(l);
+ WFunc *wfunc = (WFunc *) wfuncstate->xprstate.expr;
+ WindowStatePerFunc perfuncstate;
+ int numArguments;
+ int i;
+
+ Assert(wfunc->winlevelsup == 0);
+
+ /* Look for a previous duplicate window function */
+ for (i = 0; i <= funcno; i++)
+ {
+ if (equal(wfunc, perfunc[i].wfunc) &&
+ !contain_volatile_functions((Node *) wfunc))
+ break;
+ }
+ if (i <= funcno)
+ {
+ /* Found a match to an existing entry, so just mark it */
+ wfuncstate->funcno = i;
+ continue;
+ }
+
+ /* Nope, so assign a new PerAgg record */
+ perfuncstate = &perfunc[++funcno];
+
+ /* Mark WFunc state node with assigned index in the result array */
+ wfuncstate->funcno = funcno;
+
+ /* Fill in the perfuncstate data */
+ perfuncstate->wfuncstate = wfuncstate;
+ perfuncstate->wfunc = wfunc;
+ numArguments = list_length(wfunc->args);
+ perfuncstate->numArguments = numArguments;
+
+ fmgr_info_cxt(wfunc->winfnoid, &(perfuncstate->flinfo),
+ tmpcontext->ecxt_per_query_memory);
+ get_typlenbyval(wfunc->wintype,
+ &perfuncstate->resulttypeLen,
+ &perfuncstate->resulttypeByVal);
+
+ /*
+ * if the function doesn't have capability of window function
+ * but of aggregate, we emulate Agg environment for it.
+ */
+ perfuncstate->pure_agg = wfunc->pure_agg;
+ if (wfunc->pure_agg)
+ {
+ WindowStatePerAgg peraggstate;
+
+ perfuncstate->aggno = ++aggno;
+ peraggstate = &winstate->peragg[aggno];
+ initialize_peragg(winstate, wfunc, peraggstate);
+ peraggstate->funcno = funcno;
+
+ /* window agg -- > frame */
+ /*
+ * currently without supporting FRAME clauses,
+ * we use the partition buffering for these.
+ */
+ strategy = WINDOW_BUFFER_PARTITION;
+ }
+ else
+ {
+ /*
+ * Window functions should declare to use type of
+ * APIs for best performance in nodeWindow.
+ * Until the APIs and user-define functions are
+ * public we have fixed these function mappings.
+ */
+ switch(wfunc->winfnoid)
+ {
+ case 3898: /* row_number --> row */
+ case 3899: /* rank --> row */
+ case 3900: /* dense_rank --> row */
+ break;
+ case 3901: /* percent_rank --> partition */
+ case 3902: /* cume_dist --> partition */
+ case 3903: /* ntile --> partition */
+ case 3904: /* lag --> partition */
+ case 3905: /* lag --> partition */
+ case 3906: /* lead --> partition */
+ case 3907: /* lead --> partition */
+ strategy = WINDOW_BUFFER_PARTITION;
+ break;
+ case 3908: /* first_value --> frame */
+ case 3909: /* last_value --> frame */
+ case 3910: /* nth_value --> frame */
+ /*
+ * currently without supporting FRAME clauses,
+ * we use the partition buffering for these.
+ */
+ strategy = WINDOW_BUFFER_PARTITION;
+ break;
+ default:
+ elog(ERROR, "unknown function oid(%d)", wfunc->winfnoid);
+ }
+ }
+ }
+
+ /* Update numfuncs to match number of unique function found */
+ winstate->numfuncs = funcno + 1;
+ winstate->numaggs = aggno + 1;
+
+ winstate->strategy = strategy;
+
+ return winstate;
+ }
+
+ /* -----------------
+ * ExecCountSlotsWindow
+ * -----------------
+ */
+ int
+ ExecCountSlotsWindow(Window *node)
+ {
+ return ExecCountSlotsNode(outerPlan(node)) +
+ ExecCountSlotsNode(innerPlan(node)) +
+ WINDOW_NSLOTS;
+ }
+
+ /* -----------------
+ * ExecEndWindow
+ * -----------------
+ */
+ void
+ ExecEndWindow(WindowState *node)
+ {
+ PlanState *outerPlan;
+
+ pfree(node->perfunc);
+ pfree(node->peragg);
+ pfree(node->pergroup);
+
+ /*
+ * clear tuple before freeing expr context because
+ * tmpcontext is invalid after freeing.
+ */
+ ExecClearTuple(node->ss.ss_ScanTupleSlot);
+ ExecClearTuple(node->tmpcontext->ecxt_outertuple);
+
+ /*
+ * Free both the expr contexts.
+ */
+ ExecFreeExprContext(&node->ss.ps);
+ node->ss.ps.ps_ExprContext = node->tmpcontext;
+ ExecFreeExprContext(&node->ss.ps);
+
+ /*
+ * Free winobj after freeing its econtext (ie winstate->tmpcontext).
+ */
+ pfree(node->winobj);
+
+ if (node->prt_firstTuple != NULL)
+ heap_freetuple(node->prt_firstTuple);
+
+ MemoryContextDelete(node->wincontext);
+
+ outerPlan = outerPlanState(node);
+ ExecEndNode(outerPlan);
+ }
+
+ /* -----------------
+ * ExecRescanWindow
+ * -----------------
+ */
+ void
+ ExecReScanWindow(WindowState *node, ExprContext *exprCtxt)
+ {
+ ExprContext *econtext = node->ss.ps.ps_ExprContext;
+ int aggno;
+
+ node->win_done = false;
+
+ if (node->prt_processing)
+ release_partition(node);
+
+ if (node->prt_firstTuple != NULL)
+ {
+ heap_freetuple(node->prt_firstTuple);
+ node->prt_firstTuple = NULL;
+ }
+
+ for(aggno = 0; aggno < node->numaggs; aggno++)
+ {
+ WindowStatePerAgg peraggstate = &node->peragg[aggno];
+
+ if (peraggstate->hasResult &&
+ !peraggstate->resulttypeByVal &&
+ !peraggstate->resultValueIsNull)
+ pfree(DatumGetPointer(peraggstate->resultValue));
+ peraggstate->hasResult = false;
+ }
+
+ MemSet(econtext->ecxt_aggvalues, 0, sizeof(Datum) * node->numfuncs);
+ MemSet(econtext->ecxt_aggnulls, 0, sizeof(bool) * node->numfuncs);
+ }
+
+ /*
+ * initialize_peragg
+ *
+ * Almost same as the nodeAgg.c. We don't care DISTINCT of the aggregate
+ * argument currenlty.
+ */
+ static WindowStatePerAggData *
+ initialize_peragg(WindowState *winstate, WFunc *wfunc, WindowStatePerAgg peraggstate)
+ {
+ Oid inputTypes[FUNC_MAX_ARGS];
+ int numArguments;
+ HeapTuple aggTuple;
+ Form_pg_aggregate aggform;
+ Oid aggtranstype;
+ AclResult aclresult;
+ Oid transfn_oid,
+ finalfn_oid;
+ Expr *transfnexpr,
+ *finalfnexpr;
+ Datum textInitVal;
+ int i;
+ ListCell *lc;
+
+ numArguments = list_length(wfunc->args);
+ peraggstate->numArguments = numArguments;
+
+ i = 0;
+ foreach(lc, wfunc->args)
+ {
+ inputTypes[i++] = exprType((Node *) lfirst(lc));
+ }
+
+ aggTuple = SearchSysCache(AGGFNOID,
+ ObjectIdGetDatum(wfunc->winfnoid),
+ 0, 0, 0);
+ if (!HeapTupleIsValid(aggTuple))
+ elog(ERROR, "cache lookup failed for aggregate %u",
+ wfunc->winfnoid);
+ aggform = (Form_pg_aggregate) GETSTRUCT(aggTuple);
+
+ /* Check permission to call aggregate function */
+ aclresult = pg_proc_aclcheck(wfunc->winfnoid, GetUserId(),
+ ACL_EXECUTE);
+ if (aclresult != ACLCHECK_OK)
+ aclcheck_error(aclresult, ACL_KIND_PROC,
+ get_func_name(wfunc->winfnoid));
+
+ peraggstate->transfn_oid = transfn_oid = aggform->aggtransfn;
+ peraggstate->finalfn_oid = finalfn_oid = aggform->aggfinalfn;
+
+ /* Check that aggregate owner has permission to call component fns */
+ {
+ HeapTuple procTuple;
+ Oid aggOwner;
+
+ procTuple = SearchSysCache(PROCOID,
+ ObjectIdGetDatum(wfunc->winfnoid),
+ 0, 0, 0);
+ if (!HeapTupleIsValid(procTuple))
+ elog(ERROR, "cache lookup failed for function %u",
+ wfunc->winfnoid);
+ aggOwner = ((Form_pg_proc) GETSTRUCT(procTuple))->proowner;
+ ReleaseSysCache(procTuple);
+
+ aclresult = pg_proc_aclcheck(transfn_oid, aggOwner,
+ ACL_EXECUTE);
+ if (aclresult != ACLCHECK_OK)
+ aclcheck_error(aclresult, ACL_KIND_PROC,
+ get_func_name(transfn_oid));
+ if (OidIsValid(finalfn_oid))
+ {
+ aclresult = pg_proc_aclcheck(finalfn_oid, aggOwner,
+ ACL_EXECUTE);
+ if (aclresult != ACLCHECK_OK)
+ aclcheck_error(aclresult, ACL_KIND_PROC,
+ get_func_name(finalfn_oid));
+ }
+ }
+
+ /* resolve actual type of transition state, if polymorphic */
+ aggtranstype = aggform->aggtranstype;
+ if (IsPolymorphicType(aggtranstype))
+ {
+ /* have to fetch the agg's declared input types... */
+ Oid *declaredArgTypes;
+ int agg_nargs;
+
+ get_func_signature(wfunc->winfnoid,
+ &declaredArgTypes, &agg_nargs);
+ Assert(agg_nargs == numArguments);
+ aggtranstype = enforce_generic_type_consistency(inputTypes,
+ declaredArgTypes,
+ agg_nargs,
+ aggtranstype,
+ false);
+ pfree(declaredArgTypes);
+ }
+
+ /* build expression trees using actual argument & result types */
+ build_aggregate_fnexprs(inputTypes,
+ numArguments,
+ aggtranstype,
+ wfunc->wintype,
+ transfn_oid,
+ finalfn_oid,
+ &transfnexpr,
+ &finalfnexpr);
+
+ fmgr_info(transfn_oid, &peraggstate->transfn);
+ peraggstate->transfn.fn_expr = (Node *) transfnexpr;
+
+ if (OidIsValid(finalfn_oid))
+ {
+ fmgr_info(finalfn_oid, &peraggstate->finalfn);
+ peraggstate->finalfn.fn_expr = (Node *) finalfnexpr;
+ }
+
+ get_typlenbyval(wfunc->wintype,
+ &peraggstate->resulttypeLen,
+ &peraggstate->resulttypeByVal);
+ get_typlenbyval(aggtranstype,
+ &peraggstate->transtypeLen,
+ &peraggstate->transtypeByVal);
+
+ /*
+ * initval is potentially null, so don't try to access it as a struct
+ * field. Must do it the hard way with SysCacheGetAttr.
+ */
+ textInitVal = SysCacheGetAttr(AGGFNOID, aggTuple,
+ Anum_pg_aggregate_agginitval,
+ &peraggstate->initValueIsNull);
+
+ if (peraggstate->initValueIsNull)
+ peraggstate->initValue = (Datum) 0;
+ else
+ peraggstate->initValue = GetAggInitVal(textInitVal,
+ aggtranstype);
+
+ /*
+ * If the transfn is strict and the initval is NULL, make sure input
+ * type and transtype are the same (or at least binary-compatible), so
+ * that it's OK to use the first input value as the initial
+ * transValue. This should have been checked at agg definition time,
+ * but just in case...
+ */
+ if (peraggstate->transfn.fn_strict && peraggstate->initValueIsNull)
+ {
+ if (numArguments < 1 ||
+ !IsBinaryCoercible(inputTypes[0], aggtranstype))
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
+ errmsg("aggregate %u needs to have compatible input type and transition type",
+ wfunc->winfnoid)));
+ }
+
+ ReleaseSysCache(aggTuple);
+
+ return peraggstate;
+ }
+
+ /*
+ * is_peer
+ * compare two rows in the ORDER BY clause
+ */
+ static bool
+ is_peer(WindowState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2)
+ {
+ Window *node = (Window *) winstate->ss.ps.plan;
+
+ Assert(node->ordNumCols > 0);
+ return execTuplesMatch(slot1, slot2,
+ node->ordNumCols, node->ordColIdx,
+ winstate->ordEqfunctions,
+ winstate->tmpcontext->ecxt_per_tuple_memory);
+ }
+
+ /* window frame APIs and window iteration APIs */
+
+ /*
+ * window_seek
+ * Because tuplestore doesn't capability to seek nth row,
+ * we hold three marking points and from there advance rows as needed.
+ *
+ * The current row when seek_pos = 0 on WINDOW_SEEK_CURRENT,
+ * the first row when seek_pos = 0 on WINDOW_SEEK_HEAD,
+ * and the last row when seek_pos = 0 on WINDOW_SEEK_TAIL
+ * is fetched by the subsequent WinXXXGetArg/WinXXXGetTuple call.
+ *
+ * Since buffer may contain all the partition, window_seek is in charge
+ * of frame range boundary check.
+ */
+ static bool
+ window_seek(WindowObject winobj, int seek_pos, int seek_type, int window_type)
+ {
+ Tuplestorestate *buffer = winobj->buffer;
+ int read_pointer;
+
+ Assert(window_type == WINDOW_TYPE_FRAME || window_type == WINDOW_TYPE_PARTITION);
+ if (winobj->iterating)
+ elog(ERROR, "another iteration is going on");
+
+ switch(seek_type)
+ {
+ case WINDOW_SEEK_CURRENT:
+ read_pointer = winobj->currentptr;
+ if (window_type == WINDOW_TYPE_FRAME)
+ {
+ if (winobj->f_currentpos + seek_pos >= winobj->f_rownum)
+ return false;
+ if (winobj->f_currentpos + seek_pos < 0)
+ return false;
+ }
+ else
+ {
+ if (winobj->p_currentpos + seek_pos > winobj->p_rownum)
+ return false;
+ if (winobj->p_currentpos + seek_pos < 0)
+ return false;
+ }
+ /*
+ * Since frame->currentptr marks the next CURRENT ROW already,
+ * seek_pos is actually subtracted 1.
+ */
+ seek_pos -= 1;
+ break;
+
+ case WINDOW_SEEK_HEAD:
+ if (window_type == WINDOW_TYPE_FRAME)
+ read_pointer = winobj->f_headptr;
+ else
+ read_pointer = winobj->p_headptr;
+
+ /* validation check */
+ if (seek_pos < 0)
+ return false;
+ if (window_type == WINDOW_TYPE_FRAME)
+ {
+ if (seek_pos >= winobj->f_rownum)
+ return false;
+ }
+ break;
+
+ case WINDOW_SEEK_TAIL:
+ if (window_type == WINDOW_TYPE_FRAME)
+ read_pointer = winobj->f_tailptr;
+ else
+ read_pointer = winobj->p_tailptr;
+
+ /* validation check */
+ if (seek_pos > 0)
+ return false;
+ if (window_type == WINDOW_TYPE_FRAME)
+ {
+ if (-seek_pos >= winobj->f_rownum)
+ return false;
+ }
+ break;
+
+ default:
+ elog(ERROR, "unknown window seek type: %d", seek_type);
+ return false;
+ }
+
+ tuplestore_copy_read_pointer(buffer, read_pointer, 0);
+ if (seek_pos != 0)
+ {
+ bool forward = (seek_pos > 0);
+ int num_ahead = (seek_pos < 0 ? (-seek_pos) : seek_pos);
+ int i;
+
+ for(i = 0; i < num_ahead; i++)
+ {
+ if (!tuplestore_advance(buffer, forward))
+ {
+ /*
+ * tuplestore_advance returns false when backward scan
+ * hit the head, which is valid position.
+ * But we consider window_seek going more than head,
+ * which means the seeking position is invalid.
+ */
+ if (i < num_ahead - 1 || tuplestore_ateof(buffer))
+ return false;
+ break;
+ }
+ }
+ }
+
+ return true;
+ }
+
+ /*
+ * WinRowCurrentPos
+ * return the position of CURRENT ROW in the partition.
+ */
+ int64
+ WinRowCurrentPos(WindowObject winobj)
+ {
+ return winobj->p_currentpos;
+ }
+
+ /*
+ * WinRowGetArg
+ * return datum of the current row.
+ */
+ Datum
+ WinRowGetArg(WindowObject winobj, ExprState *argstate, bool *isnull)
+ {
+ ExprContext *econtext = winobj->econtext;
+
+ ExecStoreTuple(winobj->currentrow,
+ econtext->ecxt_outertuple,
+ InvalidBuffer,
+ false);
+ return ExecEvalExpr(argstate, econtext, isnull, NULL);
+ }
+
+ /*
+ * WinRowGetTuple
+ * fetch tuple slot of the current row. returns true if succeeded.
+ */
+ bool
+ WinRowGetTuple(WindowObject winobj, TupleTableSlot *slot)
+ {
+ ExecStoreTuple(winobj->currentrow,
+ slot,
+ InvalidBuffer,
+ false);
+ return true;
+ }
+
+ /*
+ * WinRowIsPeer
+ * compare two rows in the ORDER BY clause
+ */
+ bool
+ WinRowIsPeer(WindowObject winobj, TupleTableSlot *slot1, TupleTableSlot *slot2)
+ {
+ WindowState *winstate = winobj->winstate;
+
+ return is_peer(winstate, slot1, slot2);
+ }
+
+ /*
+ * WinFrameShrinked
+ * return true if the frame was shrinked since the last execution.
+ */
+ bool
+ WinFrameShrinked(WindowObject winobj)
+ {
+ WINDOW_CHECK_STRATEGY(winobj, WINDOW_BUFFER_FRAME);
+
+ return winobj->f_shrinked;
+ }
+
+ /*
+ * WinFrameExtended
+ * return true if the frame was extended since the last execution.
+ */
+ bool
+ WinFrameExtended(WindowObject winobj)
+ {
+ WINDOW_CHECK_STRATEGY(winobj, WINDOW_BUFFER_FRAME);
+
+ return winobj->f_extended > 0;
+ }
+
+ /*
+ * WinFrameGetRowNum
+ * return total row number of the frame.
+ */
+ int64
+ WinFrameGetRowNum(WindowObject winobj)
+ {
+ WINDOW_CHECK_STRATEGY(winobj, WINDOW_BUFFER_FRAME);
+
+ return winobj->f_rownum;
+ }
+
+ /*
+ * WinFrameGetArg
+ * return the value of the specific argument of the specific row.
+ * relpos can be positive or negative.
+ * If the target row is out of the frame, isout will be true as
+ * well as isnull.
+ */
+ Datum
+ WinFrameGetArg(WindowObject winobj, ExprState *argstate,
+ int relpos, int seektype, bool *isnull, bool *isout)
+ {
+ ExprContext *econtext = winobj->econtext;
+ TupleTableSlot *slot = econtext->ecxt_outertuple;
+ Tuplestorestate *buffer = winobj->buffer;
+
+ WINDOW_CHECK_STRATEGY(winobj, WINDOW_BUFFER_FRAME);
+
+ *isout = false;
+
+ if (!window_seek(winobj, relpos, seektype, WINDOW_TYPE_FRAME))
+ {
+ *isout = true;
+ *isnull = true;
+ return (Datum) 0;
+ }
+
+ if (!tuplestore_gettupleslot(buffer, true, slot))
+ {
+ *isout = true;
+ *isnull = true;
+ return (Datum) 0;
+ }
+
+ return ExecEvalExpr(argstate, econtext, isnull, NULL);
+ }
+
+ /*
+ * WinFrameGetTuple
+ * fetch tuple slot of the specified row.
+ * If the target row is out of the frame, isout will be true
+ * and returns false.
+ */
+ bool
+ WinFrameGetTuple(WindowObject winobj, TupleTableSlot *slot,
+ int relpos, int seektype, bool *isout)
+ {
+ Tuplestorestate *buffer = winobj->buffer;
+
+ WINDOW_CHECK_STRATEGY(winobj, WINDOW_BUFFER_FRAME);
+
+ *isout = false;
+
+ if (!window_seek(winobj, relpos, seektype, WINDOW_TYPE_FRAME))
+ {
+ *isout = true;
+ ExecClearTuple(slot);
+ return false;
+ }
+
+ if (!tuplestore_gettupleslot(buffer, true, slot))
+ {
+ *isout = true;
+ return false;
+ }
+
+ return true;
+ }
+
+ /*
+ * WinFrameShrinkingNum
+ * returns the shrinking number of the frame rows when
+ * the current frame is finishing.
+ */
+ int
+ WinFrameShrinkingNum(WindowObject winobj)
+ {
+ WINDOW_CHECK_STRATEGY(winobj, WINDOW_BUFFER_FRAME);
+
+ return winobj->f_shrinking;
+ }
+
+ /*
+ * WinFrameExtendedNum
+ * returns the extended number of the frame row when
+ * the current frame was created.
+ */
+ int
+ WinFrameExtendedNum(WindowObject winobj)
+ {
+ WINDOW_CHECK_STRATEGY(winobj, WINDOW_BUFFER_FRAME);
+
+ return winobj->f_extended;
+ }
+
+ /*
+ * WinPartGetRowNum
+ * return number of rows contained in the partition.
+ */
+ int64
+ WinPartGetRowNum(WindowObject winobj)
+ {
+ WINDOW_CHECK_STRATEGY(winobj, WINDOW_BUFFER_PARTITION);
+
+ return winobj->p_rownum;
+ }
+
+ /*
+ * WinPartGetArg
+ * return datum from the specified row in the partition.
+ * If the target row is out of the partition, isout will be true as
+ * well as isnull.
+ */
+ Datum
+ WinPartGetArg(WindowObject winobj, ExprState *argstate,
+ int relpos, int seektype, bool *isnull, bool *isout)
+ {
+ ExprContext *econtext = winobj->econtext;
+ TupleTableSlot *slot = econtext->ecxt_outertuple;
+ Tuplestorestate *buffer = winobj->buffer;
+
+ WINDOW_CHECK_STRATEGY(winobj, WINDOW_BUFFER_PARTITION);
+
+ *isout = false;
+
+ if (!window_seek(winobj, relpos, seektype, WINDOW_TYPE_PARTITION))
+ {
+ *isout = true;
+ *isnull = true;
+ return (Datum) 0;
+ }
+
+ /*
+ * Even if window_seek succeeded, it may be the last row because
+ * tuplestore doesn't report it.
+ */
+ if (!tuplestore_gettupleslot(buffer, true, slot))
+ {
+ *isout = true;
+ *isnull = true;
+ return (Datum) 0;
+ }
+
+ return ExecEvalExpr(argstate, econtext, isnull, NULL);
+ }
+
+ /*
+ * WinPartGetTuple
+ * fetch tuple slot from the specified row in the partition.
+ * If the target row is out of the frame, isout will be true
+ * and returns false.
+ */
+ bool
+ WinPartGetTuple(WindowObject winobj, TupleTableSlot *slot,
+ int relpos, int seektype, bool *isout)
+ {
+ Tuplestorestate *buffer = winobj->buffer;
+
+ WINDOW_CHECK_STRATEGY(winobj, WINDOW_BUFFER_PARTITION);
+
+ *isout = false;
+
+ if (!window_seek(winobj, relpos, seektype, WINDOW_TYPE_PARTITION))
+ {
+ *isout = true;
+ ExecClearTuple(slot);
+ return false;
+ }
+
+ if (!tuplestore_gettupleslot(buffer, true, slot))
+ {
+ *isout = true;
+ return false;
+ }
+
+ return true;
+ }
+
+ /*
+ * WinFrameStartIter
+ * initialize the frame iterator.
+ * pos is relative position from head of the frame.
+ */
+ WindowIter
+ WinFrameStartIter(WindowObject winobj, int pos)
+ {
+ WindowIterData *iter;
+
+ WINDOW_CHECK_STRATEGY(winobj, WINDOW_BUFFER_FRAME);
+
+ /*
+ * We could use Assert() here but this assumption might be
+ * broken by external API call, so use elog().
+ */
+ if (winobj->iterating)
+ elog(ERROR, "another frame iteration is not done yet.");
+
+ iter = (WindowIterData *) palloc0(sizeof(WindowIterData));
+ iter->winobj = winobj;
+ iter->type = WINDOW_TYPE_FRAME;
+ iter->position = pos;
+
+ /*
+ * seek must be done before iterating flag is set
+ */
+ window_seek(winobj, pos, WINDOW_SEEK_HEAD, iter->type);
+ iter->finished = false;
+ winobj->iterating = true;
+
+ return iter;
+ }
+
+ /*
+ * WinPartStartIter
+ * initialize the partition iterator.
+ * pos is relative position from head of the partition.
+ */
+ WindowIter
+ WinPartStartIter(WindowObject winobj, int pos)
+ {
+ WindowIterData *iter;
+
+ WINDOW_CHECK_STRATEGY(winobj, WINDOW_BUFFER_PARTITION);
+ /*
+ * We could use Assert() here but this assumption might be
+ * broken by external API call, so use elog().
+ */
+ if (winobj->iterating)
+ elog(ERROR, "another frame iteration is not done yet.");
+
+ iter = (WindowIterData *) palloc0(sizeof(WindowIterData));
+ iter->winobj = winobj;
+ iter->type = WINDOW_TYPE_PARTITION;
+ iter->position = pos;
+
+ /*
+ * seek must be done before iterating flag is set
+ */
+ window_seek(winobj, pos, WINDOW_SEEK_HEAD, iter->type);
+ iter->finished = false;
+ winobj->iterating = true;
+
+ return iter;
+ }
+
+
+ /*
+ * WinIterNext
+ * advance the iterator to the next row. Any tuple fetching is allowed
+ * after this method.
+ * return false if there is no more row.
+ */
+ bool
+ WinIterNext(WindowIter iter)
+ {
+ WindowObject winobj = iter->winobj;
+ ExprContext *econtext = winobj->econtext;
+ TupleTableSlot *slot = econtext->ecxt_outertuple;
+ bool finished = false;
+
+ if (iter->finished)
+ return false;
+
+ iter->position++;
+ if(!tuplestore_gettupleslot(winobj->buffer, true, slot))
+ {
+ finished = true;
+ }
+ else
+ {
+ /*
+ * Even though gettupeslot returns true, it could be
+ * the last row of the buffer. We track it by
+ * counting row numbers.
+ */
+ if (iter->type == WINDOW_TYPE_FRAME)
+ {
+ finished = (iter->position > winobj->f_rownum);
+ }
+ else
+ {
+ finished = (iter->position > winobj->p_rownum);
+ }
+ }
+
+ return !(iter->finished = finished);
+ }
+
+ /*
+ * WinIterFinish
+ * clean up iterator. It cannot be touched after this call.
+ */
+ void
+ WinIterFinish(WindowIter iter)
+ {
+ WindowObject winobj;
+
+ if (!iter)
+ return;
+
+ winobj = iter->winobj;
+ winobj->iterating = false;
+ pfree(iter);
+ }
+
+ /*
+ * WinIterGetArg
+ * return datum from the current iterator row.
+ */
+ Datum
+ WinIterGetArg(WindowIter iter, ExprState *argstate, bool *isnull)
+ {
+ WindowObject winobj = iter->winobj;
+ ExprContext *econtext = winobj->econtext;
+
+ return ExecEvalExpr(argstate, econtext, isnull, NULL);
+ }
+
+ /*
+ * WinIterGetTuple
+ * fetch tuple slot from the current iterator row.
+ */
+ bool
+ WinIterGetTuple(WindowIter iter, TupleTableSlot *slot)
+ {
+ TupleTableSlot *orig = iter->winobj->econtext->ecxt_outertuple;
+
+ /*
+ * winobj's outertuple has fetched the row by WinIterNext()
+ */
+ if (orig == slot)
+ return true;
+
+ ExecStoreTuple(ExecCopySlotTuple(orig), slot, InvalidBuffer, true);
+ return true;
+ }
*** a/src/backend/nodes/copyfuncs.c
--- b/src/backend/nodes/copyfuncs.c
***************
*** 762,767 **** _copyLimit(Limit *from)
--- 762,789 ----
}
/*
+ * _copyWindow
+ */
+ static Window *
+ _copyWindow(Window *from)
+ {
+ Window *newnode = makeNode(Window);
+
+ CopyPlanFields((Plan *) from, (Plan *) newnode);
+
+ COPY_SCALAR_FIELD(prtNumCols);
+ COPY_POINTER_FIELD(prtColIdx, from->prtNumCols * sizeof(AttrNumber));
+ COPY_POINTER_FIELD(prtOperators, from->prtNumCols * sizeof(Oid));
+ COPY_SCALAR_FIELD(ordNumCols);
+ COPY_POINTER_FIELD(ordColIdx, from->ordNumCols * sizeof(AttrNumber));
+ COPY_NODE_FIELD(preceding);
+ COPY_NODE_FIELD(following);
+ COPY_SCALAR_FIELD(winref);
+
+ return newnode;
+ }
+
+ /*
* _copyPlanInvalItem
*/
static PlanInvalItem *
***************
*** 932,937 **** _copyAggref(Aggref *from)
--- 954,979 ----
}
/*
+ * _copyWFunc
+ */
+ static WFunc *
+ _copyWFunc(WFunc *from)
+ {
+ WFunc *newnode = makeNode(WFunc);
+
+ COPY_SCALAR_FIELD(winfnoid);
+ COPY_SCALAR_FIELD(wintype);
+ COPY_NODE_FIELD(args);
+ COPY_SCALAR_FIELD(winlevelsup);
+ COPY_SCALAR_FIELD(winstar);
+ COPY_SCALAR_FIELD(winref);
+ COPY_SCALAR_FIELD(pure_agg);
+ COPY_LOCATION_FIELD(location);
+
+ return newnode;
+ }
+
+ /*
* _copyArrayRef
*/
static ArrayRef *
***************
*** 1730,1735 **** _copySortGroupClause(SortGroupClause *from)
--- 1772,1831 ----
return newnode;
}
+ static OrderClause *
+ _copyOrderClause(OrderClause *from)
+ {
+ OrderClause *newnode = makeNode(OrderClause);
+
+ COPY_SCALAR_FIELD(tleSortGroupRef);
+ COPY_SCALAR_FIELD(eqop);
+ COPY_SCALAR_FIELD(sortop);
+ COPY_SCALAR_FIELD(nulls_first);
+
+ return newnode;
+ }
+
+ static PartitionClause *
+ _copyPartitionClause(PartitionClause *from)
+ {
+ PartitionClause *newnode = makeNode(PartitionClause);
+
+ COPY_SCALAR_FIELD(tleSortGroupRef);
+ COPY_SCALAR_FIELD(eqop);
+ COPY_SCALAR_FIELD(sortop);
+ COPY_SCALAR_FIELD(nulls_first);
+
+ return newnode;
+ }
+
+ static WinDef *
+ _copyWinDef(WinDef *from)
+ {
+ WinDef *newnode = makeNode(WinDef);
+
+ COPY_NODE_FIELD(partitionClause);
+ COPY_NODE_FIELD(orderClause);
+ COPY_NODE_FIELD(wfunc);
+ COPY_STRING_FIELD(name);
+ COPY_LOCATION_FIELD(location);
+
+ return newnode;
+ }
+
+ static WindowClause *
+ _copyWindowClause(WindowClause *from)
+ {
+ WindowClause *newnode = makeNode(WindowClause);
+
+ COPY_NODE_FIELD(partitionClause);
+ COPY_NODE_FIELD(orderClause);
+ COPY_STRING_FIELD(name);
+ COPY_SCALAR_FIELD(has_wfunc);
+ COPY_SCALAR_FIELD(winref);
+
+ return newnode;
+ }
+
static RowMarkClause *
_copyRowMarkClause(RowMarkClause *from)
{
***************
*** 1849,1854 **** _copyFuncCall(FuncCall *from)
--- 1945,1951 ----
COPY_SCALAR_FIELD(agg_star);
COPY_SCALAR_FIELD(agg_distinct);
COPY_SCALAR_FIELD(func_variadic);
+ COPY_NODE_FIELD(win_definition);
COPY_LOCATION_FIELD(location);
return newnode;
***************
*** 2073,2078 **** _copyQuery(Query *from)
--- 2170,2176 ----
COPY_SCALAR_FIELD(hasDistinctOn);
COPY_SCALAR_FIELD(hasRecursive);
COPY_NODE_FIELD(cteList);
+ COPY_SCALAR_FIELD(hasWindow);
COPY_NODE_FIELD(rtable);
COPY_NODE_FIELD(jointree);
COPY_NODE_FIELD(targetList);
***************
*** 2081,2086 **** _copyQuery(Query *from)
--- 2179,2185 ----
COPY_NODE_FIELD(havingQual);
COPY_NODE_FIELD(distinctClause);
COPY_NODE_FIELD(sortClause);
+ COPY_NODE_FIELD(windowList);
COPY_NODE_FIELD(limitOffset);
COPY_NODE_FIELD(limitCount);
COPY_NODE_FIELD(rowMarks);
***************
*** 2141,2146 **** _copySelectStmt(SelectStmt *from)
--- 2240,2246 ----
COPY_NODE_FIELD(whereClause);
COPY_NODE_FIELD(groupClause);
COPY_NODE_FIELD(havingClause);
+ COPY_NODE_FIELD(windowClause);
COPY_NODE_FIELD(withClause);
COPY_NODE_FIELD(valuesLists);
COPY_NODE_FIELD(sortClause);
***************
*** 3326,3331 **** copyObject(void *from)
--- 3426,3433 ----
case T_Limit:
retval = _copyLimit(from);
break;
+ case T_Window:
+ retval = _copyWindow(from);
case T_PlanInvalItem:
retval = _copyPlanInvalItem(from);
break;
***************
*** 3354,3359 **** copyObject(void *from)
--- 3456,3464 ----
case T_Aggref:
retval = _copyAggref(from);
break;
+ case T_WFunc:
+ retval = _copyWFunc(from);
+ break;
case T_ArrayRef:
retval = _copyArrayRef(from);
break;
***************
*** 3828,3833 **** copyObject(void *from)
--- 3933,3950 ----
case T_SortGroupClause:
retval = _copySortGroupClause(from);
break;
+ case T_OrderClause:
+ retval = _copyOrderClause(from);
+ break;
+ case T_PartitionClause:
+ retval = _copyPartitionClause(from);
+ break;
+ case T_WinDef:
+ retval = _copyWinDef(from);
+ break;
+ case T_WindowClause:
+ retval = _copyWindowClause(from);
+ break;
case T_RowMarkClause:
retval = _copyRowMarkClause(from);
break;
*** a/src/backend/nodes/equalfuncs.c
--- b/src/backend/nodes/equalfuncs.c
***************
*** 192,197 **** _equalAggref(Aggref *a, Aggref *b)
--- 192,212 ----
}
static bool
+ _equalWFunc(WFunc *a, WFunc *b)
+ {
+ COMPARE_SCALAR_FIELD(winfnoid);
+ COMPARE_SCALAR_FIELD(wintype);
+ COMPARE_NODE_FIELD(args);
+ COMPARE_SCALAR_FIELD(winlevelsup);
+ COMPARE_SCALAR_FIELD(winstar);
+ COMPARE_SCALAR_FIELD(winref);
+ COMPARE_SCALAR_FIELD(pure_agg);
+ COMPARE_LOCATION_FIELD(location);
+
+ return true;
+ }
+
+ static bool
_equalArrayRef(ArrayRef *a, ArrayRef *b)
{
COMPARE_SCALAR_FIELD(refarraytype);
***************
*** 904,909 **** _equalSelectStmt(SelectStmt *a, SelectStmt *b)
--- 919,925 ----
COMPARE_NODE_FIELD(whereClause);
COMPARE_NODE_FIELD(groupClause);
COMPARE_NODE_FIELD(havingClause);
+ COMPARE_NODE_FIELD(windowClause);
COMPARE_NODE_FIELD(withClause);
COMPARE_NODE_FIELD(valuesLists);
COMPARE_NODE_FIELD(sortClause);
***************
*** 1799,1804 **** _equalFuncCall(FuncCall *a, FuncCall *b)
--- 1815,1821 ----
COMPARE_SCALAR_FIELD(agg_star);
COMPARE_SCALAR_FIELD(agg_distinct);
COMPARE_SCALAR_FIELD(func_variadic);
+ COMPARE_NODE_FIELD(win_definition);
COMPARE_LOCATION_FIELD(location);
return true;
***************
*** 2003,2008 **** _equalSortGroupClause(SortGroupClause *a, SortGroupClause *b)
--- 2020,2049 ----
}
static bool
+ _equalWinDef(WinDef *a, WinDef *b)
+ {
+ COMPARE_NODE_FIELD(partitionClause);
+ COMPARE_NODE_FIELD(orderClause);
+ COMPARE_NODE_FIELD(wfunc);
+ COMPARE_STRING_FIELD(name);
+ COMPARE_LOCATION_FIELD(location);
+
+ return true;
+ }
+
+ static bool
+ _equalWindowClause(WindowClause *a, WindowClause *b)
+ {
+ COMPARE_NODE_FIELD(partitionClause);
+ COMPARE_NODE_FIELD(orderClause);
+ COMPARE_STRING_FIELD(name);
+ COMPARE_SCALAR_FIELD(has_wfunc);
+ COMPARE_SCALAR_FIELD(winref);
+
+ return true;
+ }
+
+ static bool
_equalRowMarkClause(RowMarkClause *a, RowMarkClause *b)
{
COMPARE_SCALAR_FIELD(rti);
***************
*** 2204,2209 **** equal(void *a, void *b)
--- 2245,2252 ----
break;
case T_Aggref:
retval = _equalAggref(a, b);
+ case T_WFunc:
+ retval = _equalWFunc(a, b);
break;
case T_ArrayRef:
retval = _equalArrayRef(a, b);
***************
*** 2310,2315 **** equal(void *a, void *b)
--- 2353,2361 ----
case T_JoinExpr:
retval = _equalJoinExpr(a, b);
break;
+ case T_WindowClause:
+ retval = _equalWindowClause(a, b);
+ break;
/*
* RELATION NODES
***************
*** 2664,2671 **** equal(void *a, void *b)
--- 2710,2722 ----
retval = _equalRangeTblEntry(a, b);
break;
case T_SortGroupClause:
+ case T_OrderClause:
+ case T_PartitionClause:
retval = _equalSortGroupClause(a, b);
break;
+ case T_WinDef:
+ retval = _equalWinDef(a, b);
+ break;
case T_RowMarkClause:
retval = _equalRowMarkClause(a, b);
break;
*** a/src/backend/nodes/nodeFuncs.c
--- b/src/backend/nodes/nodeFuncs.c
***************
*** 52,57 **** exprType(Node *expr)
--- 52,60 ----
case T_Aggref:
type = ((Aggref *) expr)->aggtype;
break;
+ case T_WFunc:
+ type = ((WFunc *) expr)->wintype;
+ break;
case T_ArrayRef:
{
ArrayRef *arrayref = (ArrayRef *) expr;
***************
*** 1045,1050 **** expression_tree_walker(Node *node,
--- 1048,1061 ----
return true;
}
break;
+ case T_WFunc:
+ {
+ WFunc *expr = (WFunc *) node;
+ if(expression_tree_walker((Node *) expr->args,
+ walker, context))
+ return true;
+ }
+ break;
case T_ArrayRef:
{
ArrayRef *aref = (ArrayRef *) node;
***************
*** 1539,1544 **** expression_tree_mutator(Node *node,
--- 1550,1565 ----
return (Node *) newnode;
}
break;
+ case T_WFunc:
+ {
+ WFunc *wfunc = (WFunc *) node;
+ WFunc *newnode;
+
+ FLATCOPY(newnode, wfunc, WFunc);
+ MUTATE(newnode->args, wfunc->args, List *);
+ return (Node *) newnode;
+ }
+ break;
case T_ArrayRef:
{
ArrayRef *arrayref = (ArrayRef *) node;
*** a/src/backend/nodes/outfuncs.c
--- b/src/backend/nodes/outfuncs.c
***************
*** 684,689 **** _outLimit(StringInfo str, Limit *node)
--- 684,711 ----
}
static void
+ _outWindow(StringInfo str, Window *node)
+ {
+ int i;
+
+ WRITE_NODE_TYPE("WINDOW");
+
+ _outPlanInfo(str, (Plan *) node);
+
+ appendStringInfo(str, " :prtColIdx");
+ for (i = 0; i < node->prtNumCols; i++)
+ appendStringInfo(str, " %d", node->prtColIdx[i]);
+
+ appendStringInfo(str, " :prtOperations");
+ for (i = 0; i < node->prtNumCols; i++)
+ appendStringInfo(str, " %d", node->prtOperators[i]);
+
+ appendStringInfo(str, " :ordColIdx");
+ for (i = 0; i< node->ordNumCols; i++)
+ appendStringInfo(str, " %d", node->ordColIdx[i]);
+ }
+
+ static void
_outPlanInvalItem(StringInfo str, PlanInvalItem *node)
{
WRITE_NODE_TYPE("PLANINVALITEM");
***************
*** 799,804 **** _outAggref(StringInfo str, Aggref *node)
--- 821,841 ----
}
static void
+ _outWFunc(StringInfo str, WFunc *node)
+ {
+ WRITE_NODE_TYPE("WFUNC");
+
+ WRITE_OID_FIELD(winfnoid);
+ WRITE_OID_FIELD(wintype);
+ WRITE_NODE_FIELD(args);
+ WRITE_UINT_FIELD(winlevelsup);
+ WRITE_BOOL_FIELD(winstar);
+ WRITE_UINT_FIELD(winref);
+ WRITE_BOOL_FIELD(pure_agg);
+ WRITE_LOCATION_FIELD(location);
+ }
+
+ static void
_outArrayRef(StringInfo str, ArrayRef *node)
{
WRITE_NODE_TYPE("ARRAYREF");
***************
*** 1442,1447 **** _outPlannerInfo(StringInfo str, PlannerInfo *node)
--- 1479,1485 ----
WRITE_NODE_FIELD(group_pathkeys);
WRITE_NODE_FIELD(distinct_pathkeys);
WRITE_NODE_FIELD(sort_pathkeys);
+ WRITE_NODE_FIELD(window_pathkeys);
WRITE_FLOAT_FIELD(total_table_pages, "%.0f");
WRITE_FLOAT_FIELD(tuple_fraction, "%.4f");
WRITE_BOOL_FIELD(hasJoinRTEs);
***************
*** 1723,1728 **** _outSelectStmt(StringInfo str, SelectStmt *node)
--- 1761,1767 ----
WRITE_NODE_FIELD(groupClause);
WRITE_NODE_FIELD(havingClause);
WRITE_NODE_FIELD(withClause);
+ WRITE_NODE_FIELD(windowClause);
WRITE_NODE_FIELD(valuesLists);
WRITE_NODE_FIELD(sortClause);
WRITE_NODE_FIELD(limitOffset);
***************
*** 1744,1749 **** _outFuncCall(StringInfo str, FuncCall *node)
--- 1783,1789 ----
WRITE_BOOL_FIELD(agg_star);
WRITE_BOOL_FIELD(agg_distinct);
WRITE_BOOL_FIELD(func_variadic);
+ WRITE_NODE_FIELD(win_definition);
WRITE_LOCATION_FIELD(location);
}
***************
*** 1868,1873 **** _outQuery(StringInfo str, Query *node)
--- 1908,1914 ----
WRITE_BOOL_FIELD(hasAggs);
WRITE_BOOL_FIELD(hasSubLinks);
WRITE_BOOL_FIELD(hasDistinctOn);
+ WRITE_BOOL_FIELD(hasWindow);
WRITE_BOOL_FIELD(hasRecursive);
WRITE_NODE_FIELD(cteList);
WRITE_NODE_FIELD(rtable);
***************
*** 1878,1883 **** _outQuery(StringInfo str, Query *node)
--- 1919,1925 ----
WRITE_NODE_FIELD(havingQual);
WRITE_NODE_FIELD(distinctClause);
WRITE_NODE_FIELD(sortClause);
+ WRITE_NODE_FIELD(windowList);
WRITE_NODE_FIELD(limitOffset);
WRITE_NODE_FIELD(limitCount);
WRITE_NODE_FIELD(rowMarks);
***************
*** 1896,1901 **** _outSortGroupClause(StringInfo str, SortGroupClause *node)
--- 1938,1990 ----
}
static void
+ _outOrderClause(StringInfo str, OrderClause *node)
+ {
+ WRITE_NODE_TYPE("ORDERCLAUSE");
+
+ WRITE_UINT_FIELD(tleSortGroupRef);
+ WRITE_OID_FIELD(eqop);
+ WRITE_OID_FIELD(sortop);
+ WRITE_BOOL_FIELD(nulls_first);
+ }
+
+ static void
+ _outPartitionClause(StringInfo str, PartitionClause *node)
+ {
+ WRITE_NODE_TYPE("PARTITIONCLAUSE");
+
+ WRITE_UINT_FIELD(tleSortGroupRef);
+ WRITE_OID_FIELD(eqop);
+ WRITE_OID_FIELD(sortop);
+ WRITE_BOOL_FIELD(nulls_first);
+ }
+
+ static void
+ _outWinDef(StringInfo str, WinDef *node)
+ {
+ WRITE_NODE_TYPE("WINDEF");
+
+ WRITE_NODE_FIELD(partitionClause);
+ WRITE_NODE_FIELD(orderClause);
+ WRITE_NODE_FIELD(wfunc);
+ WRITE_STRING_FIELD(name);
+ WRITE_LOCATION_FIELD(location);
+ }
+
+ static void
+ _outWindowClause(StringInfo str, WindowClause *node)
+ {
+ WRITE_NODE_TYPE("WINDOWCLAUSE");
+
+ WRITE_NODE_FIELD(partitionClause);
+ WRITE_NODE_FIELD(orderClause);
+ WRITE_STRING_FIELD(name);
+ WRITE_BOOL_FIELD(has_wfunc);
+ WRITE_UINT_FIELD(winref);
+ }
+
+
+ static void
_outRowMarkClause(StringInfo str, RowMarkClause *node)
{
WRITE_NODE_TYPE("ROWMARKCLAUSE");
***************
*** 2366,2371 **** _outNode(StringInfo str, void *obj)
--- 2455,2463 ----
case T_Limit:
_outLimit(str, obj);
break;
+ case T_Window:
+ _outWindow(str, obj);
+ break;
case T_PlanInvalItem:
_outPlanInvalItem(str, obj);
break;
***************
*** 2390,2395 **** _outNode(StringInfo str, void *obj)
--- 2482,2490 ----
case T_Aggref:
_outAggref(str, obj);
break;
+ case T_WFunc:
+ _outWFunc(str, obj);
+ break;
case T_ArrayRef:
_outArrayRef(str, obj);
break;
***************
*** 2614,2619 **** _outNode(StringInfo str, void *obj)
--- 2709,2726 ----
case T_SortGroupClause:
_outSortGroupClause(str, obj);
break;
+ case T_OrderClause:
+ _outOrderClause(str, obj);
+ break;
+ case T_PartitionClause:
+ _outPartitionClause(str, obj);
+ break;
+ case T_WinDef:
+ _outWinDef(str, obj);
+ break;
+ case T_WindowClause:
+ _outWindowClause(str, obj);
+ break;
case T_RowMarkClause:
_outRowMarkClause(str, obj);
break;
*** a/src/backend/nodes/readfuncs.c
--- b/src/backend/nodes/readfuncs.c
***************
*** 155,160 **** _readQuery(void)
--- 155,161 ----
READ_BOOL_FIELD(hasAggs);
READ_BOOL_FIELD(hasSubLinks);
READ_BOOL_FIELD(hasDistinctOn);
+ READ_BOOL_FIELD(hasWindow);
READ_BOOL_FIELD(hasRecursive);
READ_NODE_FIELD(cteList);
READ_NODE_FIELD(rtable);
***************
*** 165,170 **** _readQuery(void)
--- 166,172 ----
READ_NODE_FIELD(havingQual);
READ_NODE_FIELD(distinctClause);
READ_NODE_FIELD(sortClause);
+ READ_NODE_FIELD(windowList);
READ_NODE_FIELD(limitOffset);
READ_NODE_FIELD(limitCount);
READ_NODE_FIELD(rowMarks);
***************
*** 218,223 **** _readSortGroupClause(void)
--- 220,291 ----
}
/*
+ * _readOrderClause
+ */
+ static OrderClause *
+ _readOrderClause(void)
+ {
+ READ_LOCALS(OrderClause);
+
+ READ_UINT_FIELD(tleSortGroupRef);
+ READ_OID_FIELD(eqop);
+ READ_OID_FIELD(sortop);
+ READ_BOOL_FIELD(nulls_first);
+
+ READ_DONE();
+ }
+
+ /*
+ * _readPartitionClause
+ */
+ static PartitionClause *
+ _readPartitionClause(void)
+ {
+ READ_LOCALS(PartitionClause);
+
+ READ_UINT_FIELD(tleSortGroupRef);
+ READ_OID_FIELD(eqop);
+ READ_OID_FIELD(sortop);
+ READ_BOOL_FIELD(nulls_first);
+
+ READ_DONE();
+ }
+
+ /*
+ * _readWinDef
+ */
+ static WinDef *
+ _readWinDef(void)
+ {
+ READ_LOCALS(WinDef);
+
+ READ_NODE_FIELD(partitionClause);
+ READ_NODE_FIELD(orderClause);
+ READ_NODE_FIELD(wfunc);
+ READ_STRING_FIELD(name);
+ READ_LOCATION_FIELD(location);
+
+ READ_DONE();
+ }
+
+ /*
+ * _readWindowClause
+ */
+ static WindowClause *
+ _readWindowClause(void)
+ {
+ READ_LOCALS(WindowClause);
+
+ READ_NODE_FIELD(partitionClause);
+ READ_NODE_FIELD(orderClause);
+ READ_STRING_FIELD(name);
+ READ_BOOL_FIELD(has_wfunc);
+ READ_UINT_FIELD(winref);
+
+ READ_DONE();
+ }
+
+ /*
* _readRowMarkClause
*/
static RowMarkClause *
***************
*** 401,406 **** _readAggref(void)
--- 469,494 ----
}
/*
+ * _readWFunc
+ */
+ static WFunc *
+ _readWFunc(void)
+ {
+ READ_LOCALS(WFunc);
+
+ READ_OID_FIELD(winfnoid);
+ READ_OID_FIELD(wintype);
+ READ_NODE_FIELD(args);
+ READ_UINT_FIELD(winlevelsup);
+ READ_BOOL_FIELD(winstar);
+ READ_UINT_FIELD(winref);
+ READ_BOOL_FIELD(pure_agg);
+ READ_LOCATION_FIELD(location);
+
+ READ_DONE();
+ }
+
+ /*
* _readArrayRef
*/
static ArrayRef *
***************
*** 1089,1094 **** parseNodeString(void)
--- 1177,1190 ----
return_value = _readQuery();
else if (MATCH("SORTGROUPCLAUSE", 15))
return_value = _readSortGroupClause();
+ else if (MATCH("ORDERCLAUSE", 11))
+ return_value = _readOrderClause();
+ else if (MATCH("PARTITIONCLAUSE", 15))
+ return_value = _readPartitionClause();
+ else if (MATCH("WINDEF", 6))
+ return_value = _readWinDef();
+ else if (MATCH("WINDOWCLAUSE", 12))
+ return_value = _readWindowClause();
else if (MATCH("ROWMARKCLAUSE", 13))
return_value = _readRowMarkClause();
else if (MATCH("COMMONTABLEEXPR", 15))
***************
*** 1109,1114 **** parseNodeString(void)
--- 1205,1212 ----
return_value = _readParam();
else if (MATCH("AGGREF", 6))
return_value = _readAggref();
+ else if (MATCH("WFUNC", 5))
+ return_value = _readWFunc();
else if (MATCH("ARRAYREF", 8))
return_value = _readArrayRef();
else if (MATCH("FUNCEXPR", 8))
*** a/src/backend/optimizer/path/allpaths.c
--- b/src/backend/optimizer/path/allpaths.c
***************
*** 939,945 **** standard_join_search(PlannerInfo *root, int levels_needed, List *initial_rels)
*
* Conditions checked here:
*
! * 1. If the subquery has a LIMIT clause, we must not push down any quals,
* since that could change the set of rows returned.
*
* 2. If the subquery contains EXCEPT or EXCEPT ALL set ops we cannot push
--- 939,945 ----
*
* Conditions checked here:
*
! * 1. If the subquery has a LIMIT or Window clause, we must not push down any quals,
* since that could change the set of rows returned.
*
* 2. If the subquery contains EXCEPT or EXCEPT ALL set ops we cannot push
***************
*** 960,966 **** subquery_is_pushdown_safe(Query *subquery, Query *topquery,
SetOperationStmt *topop;
/* Check point 1 */
! if (subquery->limitOffset != NULL || subquery->limitCount != NULL)
return false;
/* Are we at top level, or looking at a setop component? */
--- 960,967 ----
SetOperationStmt *topop;
/* Check point 1 */
! if (subquery->limitOffset != NULL || subquery->limitCount != NULL
! || subquery->hasWindow)
return false;
/* Are we at top level, or looking at a setop component? */
*** a/src/backend/optimizer/path/equivclass.c
--- b/src/backend/optimizer/path/equivclass.c
***************
*** 438,451 **** get_eclass_for_sort_expr(PlannerInfo *root,
/*
* add_eq_member doesn't check for volatile functions, set-returning
! * functions, or aggregates, but such could appear in sort expressions; so
! * we have to check whether its const-marking was correct.
*/
if (newec->ec_has_const)
{
if (newec->ec_has_volatile ||
expression_returns_set((Node *) expr) ||
! contain_agg_clause((Node *) expr))
{
newec->ec_has_const = false;
newem->em_is_const = false;
--- 438,454 ----
/*
* add_eq_member doesn't check for volatile functions, set-returning
! * functions, aggregates, or window functions, but such could appear
! * in sort expressions; so we have to check whether its const-marking
! * was correct.
! * XXX: need consider stable function?
*/
if (newec->ec_has_const)
{
if (newec->ec_has_volatile ||
expression_returns_set((Node *) expr) ||
! contain_agg_clause((Node *) expr) ||
! find_wfunc((Node *) expr) != NULL)
{
newec->ec_has_const = false;
newem->em_is_const = false;
*** a/src/backend/optimizer/plan/createplan.c
--- b/src/backend/optimizer/plan/createplan.c
***************
*** 3496,3501 **** make_limit(Plan *lefttree, Node *limitOffset, Node *limitCount,
--- 3496,3627 ----
return node;
}
+ /*
+ * make_window
+ * Almost same as make_agg in the meaning of partition columns
+ */
+ Window *
+ make_window(PlannerInfo *root,
+ List *tlist,
+ WindowClause *parse,
+ Oid *prtOperators,
+ Oid *ordOperators,
+ Plan *lefttree)
+ {
+ Window *node = makeNode(Window);
+ Plan *plan = &node->plan;
+ List *sub_tlist = lefttree->targetlist;
+ ListCell *lc;
+ int numCols;
+ int numWfuncs;
+
+ /*
+ * count up window functions
+ */
+ numWfuncs = 0;
+ foreach(lc, tlist)
+ {
+ TargetEntry *tle = (TargetEntry *) lfirst(lc);
+ Node *wfunc;
+
+ wfunc = find_wfunc((Node *) tle->expr);
+ if(wfunc)
+ numWfuncs++;
+ }
+
+ copy_plan_costsize(plan, lefttree);
+
+ /*
+ * Charge one cpu_operator_cost per comparison per input tuple. We assume
+ * all columns get compared at most of the tuples.
+ */
+ numCols = list_length(tlist);
+ plan->total_cost += cpu_operator_cost * lefttree->plan_rows * numCols;
+ plan->total_cost += cpu_operator_cost * numWfuncs * lefttree->plan_rows;
+
+ plan->lefttree = lefttree;
+ plan->targetlist = tlist;
+ plan->qual = NIL;
+
+ numCols = list_length(parse->partitionClause);
+ node->prtNumCols = numCols;
+ if (parse->partitionClause)
+ {
+ int keyno = 0;
+ AttrNumber *prtColIdx = NULL;
+ ListCell *pl;
+
+ prtColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
+
+ foreach(pl, parse->partitionClause)
+ {
+ PartitionClause *prtcl = (PartitionClause *) lfirst(pl);
+ Node *prtexpr = get_sortgroupclause_expr(prtcl, sub_tlist);
+ TargetEntry *te = NULL;
+ ListCell *l;
+
+ foreach(l, sub_tlist)
+ {
+ te = (TargetEntry *) lfirst(l);
+ if (equal(prtexpr, te->expr))
+ break;
+ }
+
+ Assert(te);
+ prtColIdx[keyno++] = te->resno;
+ }
+ node->prtColIdx = prtColIdx;
+ node->prtOperators = prtOperators;
+ }
+
+ numCols = list_length(parse->orderClause);
+ node->ordNumCols = numCols;
+ if (parse->orderClause)
+ {
+ int keyno = 0;
+ AttrNumber *ordColIdx = NULL;
+ ListCell *ol;
+
+ ordColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
+ foreach(ol, parse->orderClause)
+ {
+ OrderClause *ordcl = (OrderClause *) lfirst(ol);
+ Node *ordexpr = get_sortgroupclause_expr(ordcl, sub_tlist);
+ TargetEntry *te = NULL;
+ ListCell *l;
+
+ foreach(l, sub_tlist)
+ {
+ te = (TargetEntry *) lfirst(l);
+ if (equal(ordexpr, te->expr))
+ break;
+ }
+
+ Assert(te);
+ ordColIdx[keyno++] = te->resno;
+ }
+ /* orderClause columns will be used as "key columns". */
+ node->ordColIdx = ordColIdx;
+ node->ordOperators = ordOperators;
+ }
+
+ /*
+ * Currently, the parser doesn't accept frame clause.
+ * This is for future implementation.
+ */
+ node->preceding_type = FRAME_UNBOUNDED;
+ node->following_type = (node->ordNumCols > 0 ?
+ FRAME_CURRENT_RANGE : FRAME_UNBOUNDED);
+
+ node->preceding_rows = 0;
+ node->following_rows = 0;
+ node->preceding = NULL;
+ node->following = NULL;
+
+ node->winref = parse->winref;
+
+ return node;
+ }
/*
* make_result
*** a/src/backend/optimizer/plan/planagg.c
--- b/src/backend/optimizer/plan/planagg.c
***************
*** 52,57 **** static ScanDirection match_agg_to_index_col(MinMaxAggInfo *info,
--- 52,58 ----
static void make_agg_subplan(PlannerInfo *root, MinMaxAggInfo *info);
static Node *replace_aggs_with_params_mutator(Node *node, List **context);
static Oid fetch_agg_sort_op(Oid aggfnoid);
+ static bool find_aggref_walker(Node *node, Aggref **context);
/*
***************
*** 625,627 **** fetch_agg_sort_op(Oid aggfnoid)
--- 626,652 ----
return aggsortop;
}
+
+ Aggref *
+ find_aggref(Node *node)
+ {
+ Aggref *context = NULL;
+
+ find_aggref_walker(node, &context);
+ return context;
+ }
+
+ static bool
+ find_aggref_walker(Node *node, Aggref **context)
+ {
+ if (node == NULL)
+ return false;
+
+ if (IsA(node, Aggref))
+ {
+ *context = (Aggref *) node;
+ return true;
+ }
+
+ return expression_tree_walker(node, find_aggref_walker, (void *) context);
+ }
*** a/src/backend/optimizer/plan/planmain.c
--- b/src/backend/optimizer/plan/planmain.c
***************
*** 233,238 **** query_planner(PlannerInfo *root, List *tlist,
--- 233,239 ----
*/
root->query_pathkeys = canonicalize_pathkeys(root, root->query_pathkeys);
root->group_pathkeys = canonicalize_pathkeys(root, root->group_pathkeys);
+ root->window_pathkeys = canonicalize_pathkeys(root, root->window_pathkeys);
root->distinct_pathkeys = canonicalize_pathkeys(root, root->distinct_pathkeys);
root->sort_pathkeys = canonicalize_pathkeys(root, root->sort_pathkeys);
*** a/src/backend/optimizer/plan/planner.c
--- b/src/backend/optimizer/plan/planner.c
***************
*** 22,27 ****
--- 22,28 ----
#include "executor/nodeAgg.h"
#include "miscadmin.h"
#include "nodes/makefuncs.h"
+ #include "nodes/nodeFuncs.h"
#include "optimizer/clauses.h"
#include "optimizer/cost.h"
#include "optimizer/pathnode.h"
***************
*** 82,87 **** static void locate_grouping_columns(PlannerInfo *root,
--- 83,90 ----
List *sub_tlist,
AttrNumber *groupColIdx);
static List *postprocess_setop_tlist(List *new_tlist, List *orig_tlist);
+ static List *preprocess_window(List *tlist, Plan *subplan);
+ static List *window_tlist(List *tlist, Index winref, bool *has_win);
/*****************************************************************************
***************
*** 899,904 **** grouping_planner(PlannerInfo *root, double tuple_fraction)
--- 902,948 ----
else
root->group_pathkeys = NIL;
+ /*
+ * Currently we don't relocate each Window node based on
+ * cost estimation; it'd be better to think about the order
+ * of each node execution. But for now we only think about
+ * the bottom node pathkeys. This should be fixed.
+ */
+ if (parse->windowList)
+ {
+ ListCell *l;
+
+ foreach(l, parse->windowList)
+ {
+ List *partition_pathkeys = NIL;
+ List *order_pathkeys = NIL;
+ WindowClause *wc = (WindowClause *) lfirst(l);
+
+ if (wc->partitionClause &&
+ grouping_is_sortable(wc->partitionClause))
+ partition_pathkeys =
+ make_pathkeys_for_sortclauses(root,
+ wc->partitionClause,
+ tlist,
+ false);
+
+ if (wc->orderClause &&
+ grouping_is_sortable(wc->orderClause))
+ order_pathkeys =
+ make_pathkeys_for_sortclauses(root,
+ wc->orderClause,
+ tlist,
+ false);
+
+ root->window_pathkeys = list_concat(partition_pathkeys, order_pathkeys);
+ /*
+ * Window node may be stacked more than one, but
+ * what is effective to query_planner() is only the bottom pathkeys.
+ */
+ break;
+ }
+ }
+
if (parse->distinctClause &&
grouping_is_sortable(parse->distinctClause))
root->distinct_pathkeys =
***************
*** 951,956 **** grouping_planner(PlannerInfo *root, double tuple_fraction)
--- 995,1002 ----
*/
if (root->group_pathkeys)
root->query_pathkeys = root->group_pathkeys;
+ else if (root->window_pathkeys)
+ root->query_pathkeys = root->window_pathkeys;
else if (list_length(root->distinct_pathkeys) >
list_length(root->sort_pathkeys))
root->query_pathkeys = root->distinct_pathkeys;
***************
*** 1237,1242 **** grouping_planner(PlannerInfo *root, double tuple_fraction)
--- 1283,1369 ----
} /* end of if (setOperations) */
/*
+ * Window nodes are stacked one by one for each window because Window
+ * functions are evaluated in the appropriate window. Hence, in a window
+ * level, upper window expressions are replaced by nulls so as to be
+ * evaluated in the upper Window node. For lower expressions, setrefs
+ * will replace them to Var nodes.
+ */
+ if (parse->windowList)
+ {
+ ListCell *l;
+ List *window_pathkeys = NIL;
+
+ /*
+ * If the top-level plan node is one that cannot do expression
+ * evaluation, we must insert a Result node to project the
+ * desired tlist.
+ */
+ if (!is_projection_capable_plan(result_plan))
+ {
+ result_plan = (Plan *) make_result(root,
+ tlist,
+ NULL,
+ result_plan);
+ }
+ result_plan->targetlist = preprocess_window(tlist, result_plan);
+ foreach(l, parse->windowList)
+ {
+ List *current_tlist;
+ List *partition_pathkeys = NIL;
+ List *order_pathkeys = NIL;
+ WindowClause *wc = (WindowClause *) lfirst(l);
+ bool has_win = false;
+
+ current_tlist = window_tlist(tlist, wc->winref, &has_win);
+ if (!has_win)
+ continue;
+
+ /*
+ * Currently, Window partitioning is only by Sort.
+ * So just join partitionClause and orderClause
+ * to match Grouping. Hashing algorithm will be considered later.
+ */
+ if (wc->partitionClause)
+ {
+ partition_pathkeys = make_pathkeys_for_sortclauses(root,
+ wc->partitionClause,
+ result_plan->targetlist,
+ false);
+ }
+
+ if (wc->orderClause)
+ {
+ order_pathkeys = make_pathkeys_for_sortclauses(root,
+ wc->orderClause,
+ result_plan->targetlist,
+ false);
+ }
+
+ /*
+ * create Sort node under Window, so PARTITION BY works
+ */
+ window_pathkeys = list_concat(partition_pathkeys, order_pathkeys);
+ window_pathkeys = canonicalize_pathkeys(root, window_pathkeys);
+ if (!pathkeys_contained_in(window_pathkeys, current_pathkeys))
+ {
+ result_plan = (Plan *) make_sort_from_pathkeys(root,
+ result_plan,
+ window_pathkeys,
+ -1);
+ current_pathkeys = window_pathkeys;
+ }
+
+ result_plan = (Plan *) make_window(root,
+ current_tlist,
+ wc,
+ extract_grouping_ops(wc->partitionClause),
+ extract_grouping_ops(wc->orderClause),
+ result_plan);
+ }
+ }
+
+ /*
* If there is a DISTINCT clause, add the necessary node(s).
*/
if (parse->distinctClause)
***************
*** 2039,2045 **** make_subplanTargetList(PlannerInfo *root,
* If we're not grouping or aggregating, there's nothing to do here;
* query_planner should receive the unmodified target list.
*/
! if (!parse->hasAggs && !parse->groupClause && !root->hasHavingQual)
{
*need_tlist_eval = true;
return tlist;
--- 2166,2172 ----
* If we're not grouping or aggregating, there's nothing to do here;
* query_planner should receive the unmodified target list.
*/
! if (!parse->hasAggs && !parse->groupClause && !root->hasHavingQual && !parse->hasWindow)
{
*need_tlist_eval = true;
return tlist;
***************
*** 2199,2201 **** postprocess_setop_tlist(List *new_tlist, List *orig_tlist)
--- 2326,2513 ----
elog(ERROR, "resjunk output columns are not implemented");
return new_tlist;
}
+
+ /*
+ * preprocess_window -
+ * given parser tlist, returns recomposed tlist for current top plan.
+ *
+ * Before create Window nodes, window expressions are removed from current
+ * tlist because current plan must not be a Window node. These expressions
+ * are evaluated in appropriate window later.
+ *
+ * There are two main cases to be considered.
+ * 1. Agg/Group
+ * Vars from scan node required by any of expression should have been pulled
+ * up to now. So there's no need to consider it.
+ *
+ * 2. Other Scan
+ * The situation resembles to the one in Agg/Group. Var expressions are pulled
+ * (tlist is flattened), and other evaluation expressions but window expression
+ * are as well, since in Window nodes we take care of only window expression.
+ *
+ * common in both
+ * WFunc args are also pulled and appended to the subplan. The window functions
+ * assume their arguments must be Var or Const, retrieved from outer plan.
+ */
+ static List *
+ preprocess_window(List *tlist, Plan *subplan)
+ {
+ ListCell *l;
+ List *pulled_exprs = NIL;
+ List *output_targetlist = NIL;
+ AttrNumber resno,
+ tlist_resno;
+
+ /*
+ * Agg/Group has already flatten its tlist. Only other nodes
+ * must consider pulling vars.
+ */
+ if (!(IsA(subplan, Agg) || IsA(subplan, Group)))
+ {
+ /*
+ * copyObject() is required, as in tlist = lappend(tlist, tle);
+ * Without this, it may fall into an infinte loop.
+ */
+ output_targetlist = copyObject(flatten_tlist(tlist));
+ tlist_resno = list_length(tlist);
+
+ foreach(l, output_targetlist)
+ {
+ TargetEntry *tle = (TargetEntry *) lfirst(l);
+ TargetEntry *member;
+ Var *var = (Var *) tle->expr;
+
+ /*
+ * tlist must have full set of vars required
+ * by any window functions up to the top Window node.
+ */
+ member = tlist_member((Node *) var, tlist);
+ if (!member)
+ {
+ tlist_resno++;
+ tle = makeTargetEntry(copyObject(var),
+ tlist_resno,
+ NULL,
+ true);
+ tlist = lappend(tlist, tle);
+ }
+ else
+ {
+ /*
+ * It is necessary since flatten_tlist() doesn't pull
+ * their resosortgroupref.
+ */
+ tle->ressortgroupref = member->ressortgroupref;
+ }
+ }
+ }
+
+ resno = list_length(output_targetlist);
+ foreach(l, tlist)
+ {
+ TargetEntry *tle = (TargetEntry *) lfirst(l);
+ TargetEntry *newtle;
+ WFunc *wfunc;
+
+ /*
+ * WFuncs doesn't work in the current top plan. So
+ * we replace these nodes to NullConst but save their
+ * args in order that WFuncs argument evaluations contain
+ * only Var and Const.
+ */
+ wfunc = (WFunc *) find_wfunc((Node *) tle->expr);
+ if (wfunc)
+ {
+ pulled_exprs = list_concat(pulled_exprs, wfunc->args);
+ tle = flatCopyTargetEntry(tle);
+ tle->expr = (Expr *) makeNullConst(exprType((Node *) tle->expr),
+ exprTypmod((Node *) tle->expr));
+ }
+
+ if (tlist_member((Node *) tle->expr, output_targetlist))
+ continue;
+
+ /*
+ * If an entry isn't in flatten tlist nor window expression,
+ * it must be evaluated here before any of Window nodes.
+ */
+ newtle = flatCopyTargetEntry(tle);
+ resno++;
+ newtle->resno = resno;
+ output_targetlist = lappend(output_targetlist, newtle);
+ }
+
+ tlist_resno = list_length(tlist);
+ /*
+ * finally pulled arguments are appended to the current tlist so that
+ * each window function can take Var or Const arguments.
+ */
+ foreach(l, pulled_exprs)
+ {
+ TargetEntry *tle;
+ Expr *expr = (Expr *) lfirst(l);
+
+ resno++;
+ tle = makeTargetEntry(expr,
+ resno,
+ NULL,
+ true);
+ output_targetlist = lappend(output_targetlist, tle);
+
+ /*
+ * We also need the entry in the middle windows,
+ * so that upper window can take them as arguments.
+ */
+ if (!tlist_member((Node *) tle->expr, tlist))
+ {
+ tle = flatCopyTargetEntry(tle);
+ tlist_resno++;
+ tle->resno = tlist_resno;
+ tlist = lappend(tlist, tle);
+ }
+ }
+
+ return output_targetlist;
+ }
+
+ /*
+ * window_tlist -
+ *
+ * creates tlist suitable for the current window, indicated by winref.
+ * For the upper window expressions than current, they are relpaced
+ * by NullConst, so that setrefs can understand where the references
+ * may stop.
+ * With window clause syntax, there may be a window in which none of
+ * window evaluations is executed. In this case, we can pass by the window.
+ */
+ static List *
+ window_tlist(List *tlist, Index winref, bool *has_win)
+ {
+ List *output_targetlist = NIL;
+ ListCell *l;
+
+ foreach(l, tlist)
+ {
+ TargetEntry *tle = (TargetEntry *) lfirst(l);
+ WFunc *wfunc;
+
+ tle = flatCopyTargetEntry(tle);
+ wfunc = (WFunc *) find_wfunc_greater((Node *) tle->expr);
+ if (wfunc && winref == wfunc->winref)
+ *has_win = true;
+
+ /*
+ * window that contains evaluation on upper than current window is set null.
+ * for the lower ones, setrefs will fix them to Vars pointing to OUTER.
+ */
+ if (wfunc && winref < wfunc->winref)
+ {
+ tle->expr = (Expr *) makeNullConst(exprType((Node *) tle->expr),
+ exprTypmod((Node *) tle->expr));
+ }
+
+ output_targetlist = lappend(output_targetlist, tle);
+ }
+
+ return output_targetlist;
+ }
*** a/src/backend/optimizer/plan/setrefs.c
--- b/src/backend/optimizer/plan/setrefs.c
***************
*** 416,421 **** set_plan_refs(PlannerGlobal *glob, Plan *plan, int rtoffset)
--- 416,422 ----
break;
case T_Agg:
case T_Group:
+ case T_Window:
set_upper_references(glob, plan, rtoffset);
break;
case T_Result:
*** a/src/backend/optimizer/plan/subselect.c
--- b/src/backend/optimizer/plan/subselect.c
***************
*** 1954,1959 **** finalize_plan(PlannerInfo *root, Plan *plan, Bitmapset *valid_params)
--- 1954,1960 ----
case T_Unique:
case T_SetOp:
case T_Group:
+ case T_Window:
break;
default:
*** a/src/backend/optimizer/prep/prepjointree.c
--- b/src/backend/optimizer/prep/prepjointree.c
***************
*** 937,942 **** is_simple_subquery(Query *subquery)
--- 937,943 ----
* limiting, or WITH. (XXX WITH could possibly be allowed later)
*/
if (subquery->hasAggs ||
+ subquery->hasWindow ||
subquery->groupClause ||
subquery->havingQual ||
subquery->sortClause ||
*** a/src/backend/optimizer/util/clauses.c
--- b/src/backend/optimizer/util/clauses.c
***************
*** 780,785 **** contain_volatile_functions_walker(Node *node, void *context)
--- 780,793 ----
return true;
/* else fall through to check args */
}
+ else if (IsA(node, WFunc))
+ {
+ WFunc *winagg = (WFunc *) node;
+
+ if (func_volatile(winagg->winfnoid) == PROVOLATILE_VOLATILE)
+ return true;
+ /* else fall through to check args */
+ }
else if (IsA(node, OpExpr))
{
OpExpr *expr = (OpExpr *) node;
*** a/src/backend/optimizer/util/tlist.c
--- b/src/backend/optimizer/util/tlist.c
***************
*** 366,368 **** grouping_is_hashable(List *groupClause)
--- 366,369 ----
}
return true;
}
+
*** a/src/backend/optimizer/util/var.c
--- b/src/backend/optimizer/util/var.c
***************
*** 65,70 **** typedef struct
--- 65,76 ----
int sublevels_up;
} flatten_join_alias_vars_context;
+ typedef struct
+ {
+ Node *node;
+ int prefer;
+ } find_wfunc_context;
+
static bool pull_varnos_walker(Node *node,
pull_varnos_context *context);
static bool pull_varattnos_walker(Node *node, Bitmapset **varattnos);
***************
*** 81,86 **** static bool pull_var_clause_walker(Node *node,
--- 87,94 ----
static Node *flatten_join_alias_vars_mutator(Node *node,
flatten_join_alias_vars_context *context);
static Relids alias_relid_set(PlannerInfo *root, Relids relids);
+ static Node *find_wfunc_inner(Node *node, int prefer);
+ static bool find_wfunc_walker(Node *node, find_wfunc_context *context);
/*
***************
*** 848,850 **** alias_relid_set(PlannerInfo *root, Relids relids)
--- 856,937 ----
bms_free(tmprelids);
return result;
}
+
+ /*
+ * Since a target entry may contain more than one window function,
+ * caller can specify which window function is demanded.
+ */
+ Node *
+ find_wfunc_greater(Node *node)
+ {
+ return find_wfunc_inner(node, 1);
+ }
+
+ Node *
+ find_wfunc_lesser(Node *node)
+ {
+ return find_wfunc_inner(node, -1);
+ }
+
+ Node *
+ find_wfunc(Node *node)
+ {
+ return find_wfunc_inner(node, 0);
+ }
+
+ /*
+ * find_wfunc -
+ * find window function node in the given TargetEntry.
+ * parameter prefer means caller prefers greater winref in > 0 and
+ * lesser winref in < 0. prefer 0 means no care.
+ */
+ static Node *
+ find_wfunc_inner(Node *node, int prefer)
+ {
+ find_wfunc_context context;
+
+ context.node = NULL;
+ context.prefer = prefer;
+ find_wfunc_walker(node, &context);
+
+ return context.node;
+ }
+
+ /*
+ * find_wfunc_walker -
+ */
+ static bool
+ find_wfunc_walker(Node *node, find_wfunc_context *context)
+ {
+ if (node == NULL)
+ return false;
+
+ if (IsA(node, WFunc))
+ {
+ if (context->node)
+ {
+ if (context->prefer > 0)
+ {
+ if (((WFunc *) context->node)->winref < ((WFunc *) node)->winref)
+ context->node = node;
+ }
+ else
+ {
+ /* context->node != NULL && context->prefer == 0 doesn't make sense */
+ if (((WFunc *) context->node)->winref > ((WFunc *) node)->winref)
+ context->node = node;
+ }
+ }
+ else
+ context->node = node;
+
+ /*
+ * no prefer, which means no need to search others.
+ * let's return the first found node.
+ */
+ if (context->prefer == 0)
+ return true;
+ }
+
+ return expression_tree_walker(node, find_wfunc_walker, (void *) context);
+ }
*** a/src/backend/parser/analyze.c
--- b/src/backend/parser/analyze.c
***************
*** 779,784 **** transformSelectStmt(ParseState *pstate, SelectStmt *stmt)
--- 779,789 ----
qry->hasDistinctOn = true;
}
+ pstate->p_windef_list = list_concat(stmt->windowClause, pstate->p_windef_list);
+ qry->windowList = transformWinDef(pstate,
+ pstate->p_windef_list,
+ &qry->targetList);
+
/* transform LIMIT */
qry->limitOffset = transformLimitClause(pstate, stmt->limitOffset,
"OFFSET");
***************
*** 798,806 **** transformSelectStmt(ParseState *pstate, SelectStmt *stmt)
--- 803,815 ----
qry->hasSubLinks = pstate->p_hasSubLinks;
qry->hasAggs = pstate->p_hasAggs;
+ qry->hasWindow = pstate->p_hasWindow;
if (pstate->p_hasAggs || qry->groupClause || qry->havingQual)
parseCheckAggregates(pstate, qry);
+ if (pstate->p_hasWindow)
+ parseCheckWindow(pstate, qry);
+
foreach(l, stmt->lockingClause)
{
transformLockingClause(pstate, qry, (LockingClause *) lfirst(l));
***************
*** 1564,1571 **** transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt)
qry->hasSubLinks = pstate->p_hasSubLinks;
/*
! * Top-level aggregates are simply disallowed in UPDATE, per spec. (From
! * an implementation point of view, this is forced because the implicit
* ctid reference would otherwise be an ungrouped variable.)
*/
if (pstate->p_hasAggs)
--- 1573,1580 ----
qry->hasSubLinks = pstate->p_hasSubLinks;
/*
! * Top-level aggregates nor window are simply disallowed in UPDATE, per spec.
! * (From an implementation point of view, this is forced because the implicit
* ctid reference would otherwise be an ungrouped variable.)
*/
if (pstate->p_hasAggs)
***************
*** 1575,1580 **** transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt)
--- 1584,1594 ----
parser_errposition(pstate,
locate_agg_of_level((Node *) qry, 0))));
+ if (pstate->p_hasWindow)
+ ereport(ERROR,
+ (errcode(ERRCODE_WINDOWING_ERROR),
+ errmsg("cannot use window function in UPDATE")));
+
/*
* Now we are done with SELECT-like processing, and can get on with
* transforming the target list to match the UPDATE target columns.
***************
*** 1674,1679 **** transformReturningList(ParseState *pstate, List *returningList)
--- 1688,1699 ----
parser_errposition(pstate,
locate_agg_of_level((Node *) rlist, 0))));
+ /* window functions not allowed in returning clause */
+ if (pstate->p_hasWindow)
+ ereport(ERROR,
+ (errcode(ERRCODE_WINDOWING_ERROR),
+ errmsg("cannot use window function in RETURNING")));
+
/* no new relation references please */
if (list_length(pstate->p_rtable) != length_rtable)
{
*** a/src/backend/parser/gram.y
--- b/src/backend/parser/gram.y
***************
*** 385,390 **** static TypeName *TableFuncTypeName(List *columns);
--- 385,395 ----
%type with_clause
%type cte_list
+ %type partition_clause opt_partition_clause window_clause window_definition_list
+ %type window_definition window_specification over_clause
+ /* since these are not implemented, types may be unmatched actually. */
+ %type opt_frame_clause frame_clause frame_extent
+ %type frame_bound_const frame_bound opt_frame_exclusion
/*
* If you make any token changes, update the keyword table in
***************
*** 414,423 **** static TypeName *TableFuncTypeName(List *columns);
DEFERRABLE DEFERRED DEFINER DELETE_P DELIMITER DELIMITERS DESC
DICTIONARY DISABLE_P DISCARD DISTINCT DO DOCUMENT_P DOMAIN_P DOUBLE_P DROP
! EACH ELSE ENABLE_P ENCODING ENCRYPTED END_P ENUM_P ESCAPE EXCEPT EXCLUDING
! EXCLUSIVE EXECUTE EXISTS EXPLAIN EXTERNAL EXTRACT
! FALSE_P FAMILY FETCH FIRST_P FLOAT_P FOR FORCE FOREIGN FORWARD
FREEZE FROM FULL FUNCTION
GLOBAL GRANT GRANTED GREATEST GROUP_P
--- 419,428 ----
DEFERRABLE DEFERRED DEFINER DELETE_P DELIMITER DELIMITERS DESC
DICTIONARY DISABLE_P DISCARD DISTINCT DO DOCUMENT_P DOMAIN_P DOUBLE_P DROP
! EACH ELSE ENABLE_P ENCODING ENCRYPTED END_P ENUM_P ESCAPE EXCEPT EXCLUDE
! EXCLUDING EXCLUSIVE EXECUTE EXISTS EXPLAIN EXTERNAL EXTRACT
! FALSE_P FAMILY FETCH FIRST_P FLOAT_P FOLLOWING FOR FORCE FOREIGN FORWARD
FREEZE FROM FULL FUNCTION
GLOBAL GRANT GRANTED GREATEST GROUP_P
***************
*** 444,458 **** static TypeName *TableFuncTypeName(List *columns);
NOT NOTHING NOTIFY NOTNULL NOWAIT NULL_P NULLIF NULLS_P NUMERIC
OBJECT_P OF OFF OFFSET OIDS OLD ON ONLY OPERATOR OPTION OR
! ORDER OUT_P OUTER_P OVERLAPS OVERLAY OWNED OWNER
! PARSER PARTIAL PASSWORD PLACING PLANS POSITION
! PRECISION PRESERVE PREPARE PREPARED PRIMARY
PRIOR PRIVILEGES PROCEDURAL PROCEDURE
QUOTE
! READ REAL REASSIGN RECHECK RECURSIVE REFERENCES REINDEX RELATIVE_P RELEASE
RENAME REPEATABLE REPLACE REPLICA RESET RESTART RESTRICT RETURNING RETURNS
REVOKE RIGHT ROLE ROLLBACK ROW ROWS RULE
--- 449,463 ----
NOT NOTHING NOTIFY NOTNULL NOWAIT NULL_P NULLIF NULLS_P NUMERIC
OBJECT_P OF OFF OFFSET OIDS OLD ON ONLY OPERATOR OPTION OR
! ORDER OTHERS OUT_P OUTER_P OVER OVERLAPS OVERLAY OWNED OWNER
! PARSER PARTIAL PARTITION PASSWORD PLACING PLANS POSITION
! PRECEDING PRECISION PRESERVE PREPARE PREPARED PRIMARY
PRIOR PRIVILEGES PROCEDURAL PROCEDURE
QUOTE
! RANGE READ REAL REASSIGN RECHECK RECURSIVE REFERENCES REINDEX RELATIVE_P RELEASE
RENAME REPEATABLE REPLACE REPLICA RESET RESTART RESTRICT RETURNING RETURNS
REVOKE RIGHT ROLE ROLLBACK ROW ROWS RULE
***************
*** 462,478 **** static TypeName *TableFuncTypeName(List *columns);
STATISTICS STDIN STDOUT STORAGE STRICT_P STRIP_P SUBSTRING SUPERUSER_P
SYMMETRIC SYSID SYSTEM_P
! TABLE TABLESPACE TEMP TEMPLATE TEMPORARY TEXT_P THEN TIME TIMESTAMP
TO TRAILING TRANSACTION TREAT TRIGGER TRIM TRUE_P
TRUNCATE TRUSTED TYPE_P
! UNCOMMITTED UNENCRYPTED UNION UNIQUE UNKNOWN UNLISTEN UNTIL
UPDATE USER USING
VACUUM VALID VALIDATOR VALUE_P VALUES VARCHAR VARIADIC VARYING
VERBOSE VERSION_P VIEW VOLATILE
! WHEN WHERE WHITESPACE_P WITH WITHOUT WORK WRITE
XML_P XMLATTRIBUTES XMLCONCAT XMLELEMENT XMLFOREST XMLPARSE
XMLPI XMLROOT XMLSERIALIZE
--- 467,483 ----
STATISTICS STDIN STDOUT STORAGE STRICT_P STRIP_P SUBSTRING SUPERUSER_P
SYMMETRIC SYSID SYSTEM_P
! TABLE TABLESPACE TEMP TEMPLATE TEMPORARY TEXT_P THEN TIES TIME TIMESTAMP
TO TRAILING TRANSACTION TREAT TRIGGER TRIM TRUE_P
TRUNCATE TRUSTED TYPE_P
! UNBOUNDED UNCOMMITTED UNENCRYPTED UNION UNIQUE UNKNOWN UNLISTEN UNTIL
UPDATE USER USING
VACUUM VALID VALIDATOR VALUE_P VALUES VARCHAR VARIADIC VARYING
VERBOSE VERSION_P VIEW VOLATILE
! WHEN WHERE WHITESPACE_P WINDOW WITH WITHOUT WORK WRITE
XML_P XMLATTRIBUTES XMLCONCAT XMLELEMENT XMLFOREST XMLPARSE
XMLPI XMLROOT XMLSERIALIZE
***************
*** 506,512 **** static TypeName *TableFuncTypeName(List *columns);
%nonassoc BETWEEN
%nonassoc IN_P
%left POSTFIXOP /* dummy for postfix Op rules */
! %nonassoc IDENT /* to support target_el without AS */
%left Op OPERATOR /* multi-character ops and user-defined operators */
%nonassoc NOTNULL
%nonassoc ISNULL
--- 511,521 ----
%nonassoc BETWEEN
%nonassoc IN_P
%left POSTFIXOP /* dummy for postfix Op rules */
! /*
! * - to support target_el without AS (IDENT)
! * - to support frame_clause starting ROWS/RANGE
! */
! %nonassoc IDENT ROWS RANGE
%left Op OPERATOR /* multi-character ops and user-defined operators */
%nonassoc NOTNULL
%nonassoc ISNULL
***************
*** 6424,6430 **** select_clause:
simple_select:
SELECT opt_distinct target_list
into_clause from_clause where_clause
! group_clause having_clause
{
SelectStmt *n = makeNode(SelectStmt);
n->distinctClause = $2;
--- 6433,6439 ----
simple_select:
SELECT opt_distinct target_list
into_clause from_clause where_clause
! group_clause having_clause window_clause
{
SelectStmt *n = makeNode(SelectStmt);
n->distinctClause = $2;
***************
*** 6434,6439 **** simple_select:
--- 6443,6449 ----
n->whereClause = $6;
n->groupClause = $7;
n->havingClause = $8;
+ n->windowClause = $9;
$$ = (Node *)n;
}
| values_clause { $$ = $1; }
***************
*** 8202,8208 **** c_expr: columnref { $$ = $1; }
* (Note that many of the special SQL functions wouldn't actually make any
* sense as functional index entries, but we ignore that consideration here.)
*/
! func_expr: func_name '(' ')'
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
--- 8212,8218 ----
* (Note that many of the special SQL functions wouldn't actually make any
* sense as functional index entries, but we ignore that consideration here.)
*/
! func_expr: func_name '(' ')' over_clause
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
***************
*** 8210,8219 **** func_expr: func_name '(' ')'
n->agg_star = FALSE;
n->agg_distinct = FALSE;
n->func_variadic = FALSE;
n->location = @1;
$$ = (Node *)n;
}
! | func_name '(' expr_list ')'
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
--- 8220,8230 ----
n->agg_star = FALSE;
n->agg_distinct = FALSE;
n->func_variadic = FALSE;
+ n->win_definition = (WinDef *) $4;
n->location = @1;
$$ = (Node *)n;
}
! | func_name '(' expr_list ')' over_clause
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
***************
*** 8221,8230 **** func_expr: func_name '(' ')'
n->agg_star = FALSE;
n->agg_distinct = FALSE;
n->func_variadic = FALSE;
n->location = @1;
$$ = (Node *)n;
}
! | func_name '(' VARIADIC a_expr ')'
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
--- 8232,8242 ----
n->agg_star = FALSE;
n->agg_distinct = FALSE;
n->func_variadic = FALSE;
+ n->win_definition = (WinDef *) $5;
n->location = @1;
$$ = (Node *)n;
}
! | func_name '(' VARIADIC a_expr ')' /* intentionally not accept over_clause */
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
***************
*** 8232,8241 **** func_expr: func_name '(' ')'
n->agg_star = FALSE;
n->agg_distinct = FALSE;
n->func_variadic = TRUE;
n->location = @1;
$$ = (Node *)n;
}
! | func_name '(' expr_list ',' VARIADIC a_expr ')'
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
--- 8244,8254 ----
n->agg_star = FALSE;
n->agg_distinct = FALSE;
n->func_variadic = TRUE;
+ n->win_definition = NULL;
n->location = @1;
$$ = (Node *)n;
}
! | func_name '(' expr_list ',' VARIADIC a_expr ')' /* intentionally not accept over_clause */
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
***************
*** 8243,8252 **** func_expr: func_name '(' ')'
n->agg_star = FALSE;
n->agg_distinct = FALSE;
n->func_variadic = TRUE;
n->location = @1;
$$ = (Node *)n;
}
! | func_name '(' ALL expr_list ')'
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
--- 8256,8266 ----
n->agg_star = FALSE;
n->agg_distinct = FALSE;
n->func_variadic = TRUE;
+ n->win_definition = NULL;
n->location = @1;
$$ = (Node *)n;
}
! | func_name '(' ALL expr_list ')' /* intentionally not accept over_clause */
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
***************
*** 8258,8267 **** func_expr: func_name '(' ')'
* for that in FuncCall at the moment.
*/
n->func_variadic = FALSE;
n->location = @1;
$$ = (Node *)n;
}
! | func_name '(' DISTINCT expr_list ')'
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
--- 8272,8282 ----
* for that in FuncCall at the moment.
*/
n->func_variadic = FALSE;
+ n->win_definition = NULL;
n->location = @1;
$$ = (Node *)n;
}
! | func_name '(' DISTINCT expr_list ')' /* intentionally not accept over_clause */
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
***************
*** 8269,8278 **** func_expr: func_name '(' ')'
n->agg_star = FALSE;
n->agg_distinct = TRUE;
n->func_variadic = FALSE;
n->location = @1;
$$ = (Node *)n;
}
! | func_name '(' '*' ')'
{
/*
* We consider AGGREGATE(*) to invoke a parameterless
--- 8284,8294 ----
n->agg_star = FALSE;
n->agg_distinct = TRUE;
n->func_variadic = FALSE;
+ n->win_definition = NULL;
n->location = @1;
$$ = (Node *)n;
}
! | func_name '(' '*' ')' over_clause
{
/*
* We consider AGGREGATE(*) to invoke a parameterless
***************
*** 8290,8295 **** func_expr: func_name '(' ')'
--- 8306,8312 ----
n->agg_star = TRUE;
n->agg_distinct = FALSE;
n->func_variadic = FALSE;
+ n->win_definition = (WinDef *) $5;
n->location = @1;
$$ = (Node *)n;
}
***************
*** 8737,8742 **** xml_whitespace_option: PRESERVE WHITESPACE_P { $$ = TRUE; }
--- 8754,8908 ----
;
/*
+ * Window Definitions
+ *
+ * In SQL2003 window may appear after a function call or after HAVING, with the same syntax.
+ * If there is window syntax after HAVING, some of the windows can refer to it.
+ */
+ over_clause: OVER window_specification { $$ = $2; }
+ | OVER IDENT
+ {
+ WinDef *n = makeNode(WinDef);
+ n->partitionClause = NIL;
+ n->orderClause = NIL;
+ n->wfunc = NULL;
+ n->name = pstrdup($2);
+ n->location = @1;
+ $$ = (Node *) n;
+ }
+ | /*EMPTY*/ { $$ = NULL; }
+ ;
+ window_specification: '(' opt_partition_clause opt_sort_clause opt_frame_clause')'
+ {
+ WinDef *n = makeNode(WinDef);
+ n->partitionClause = $2;
+ n->orderClause = $3;
+ n->wfunc = NULL;
+ n->name = NULL;
+ n->location = @1;
+ $$ = (Node *) n;
+ }
+ ;
+
+ opt_partition_clause:
+ partition_clause { $$ = $1; }
+ | /*EMPTY*/ { $$ = NIL; }
+ ;
+ partition_clause: PARTITION BY expr_list
+ {
+ $$ = $3;
+ }
+ ;
+
+ /* Frame clause is not supported but we must recognize its grammar to report errors */
+ opt_frame_clause:
+ frame_clause
+ {
+ /* Frame clause should be called "FRAME clause" or "ROWS/RANGE clause"? */
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("ROWS/RANGE clause of window functions not yet implemented")));
+ }
+ | /*EMPTY*/ { $$ = NULL; }
+ ;
+ frame_clause:
+ ROWS frame_extent opt_frame_exclusion
+ {
+ $$ = NULL;
+ }
+ | RANGE frame_extent opt_frame_exclusion
+ {
+ $$ = NULL;
+ }
+ ;
+ /*
+ * frame_bound_const is redundant but needed instead of AexprConst, since
+ * AexprConst contains func_name which is sometimes BETWEEN
+ * and if so shift/reduce conflict occurs. But frame_bound doesn't
+ * need func_name.
+ */
+ frame_extent:
+ UNBOUNDED PRECEDING { $$ = NULL; }
+ | CURRENT_P ROW { $$ = NULL; }
+ | frame_bound_const PRECEDING { $$ = NULL; }
+ | BETWEEN frame_bound AND frame_bound { $$ = NULL; }
+ ;
+ frame_bound:
+ UNBOUNDED PRECEDING { $$ = NULL; }
+ | CURRENT_P ROW { $$ = NULL; }
+ | frame_bound_const PRECEDING { $$ = NULL; }
+ | UNBOUNDED FOLLOWING { $$ = NULL; }
+ | frame_bound_const FOLLOWING { $$ = NULL; }
+ ;
+ /*
+ * similar to AexprConst except func_name
+ */
+ frame_bound_const:
+ Iconst { $$ = makeIntConst($1, @1); }
+ | FCONST { $$ = makeFloatConst($1, @1); }
+ | Sconst { $$ = makeStringConst($1, @1); }
+ | BCONST { $$ = makeBitStringConst($1, @1); }
+ | XCONST { $$ = makeBitStringConst($1, @1); }
+ | ConstTypename Sconst { $$ = makeStringConstCast($2, @2, $1); }
+ | ConstInterval Sconst opt_interval
+ {
+ TypeName *t = $1;
+ t->typmods = $3;
+ $$ = makeStringConstCast($2, @2, t);
+ }
+ | ConstInterval '(' Iconst ')' Sconst opt_interval
+ {
+ TypeName *t = $1;
+ if ($6 != NIL)
+ {
+ if (list_length($6) != 1)
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("interval precision specified twice"),
+ scanner_errposition(@1)));
+ t->typmods = lappend($6, makeIntConst($3, @3));
+ }
+ else
+ t->typmods = list_make2(makeIntConst(INTERVAL_FULL_RANGE, -1),
+ makeIntConst($3, @3));
+ $$ = makeStringConstCast($5, @5, t);
+ }
+ | TRUE_P { $$ = makeBoolAConst(TRUE, @1); }
+ | FALSE_P { $$ = makeBoolAConst(FALSE, @1); }
+ | NULL_P { $$ = makeNullAConst(@1); }
+ ;
+ opt_frame_exclusion:
+ EXCLUDE CURRENT_P ROW { $$ = NULL; }
+ | EXCLUDE GROUP_P { $$ = NULL; }
+ | EXCLUDE TIES { $$ = NULL; }
+ | EXCLUDE NO OTHERS { $$ = NULL; }
+ | /*EMPTY*/ { $$ = NULL; }
+ ;
+
+ window_clause:
+ WINDOW window_definition_list { $$ = $2; }
+ | /*EMPTY*/ { $$ = NIL; }
+ ;
+ window_definition_list:
+ window_definition
+ {
+ $$ = list_make1($1);
+ }
+ | window_definition_list ',' window_definition
+ {
+ $$ = lappend($1, $3);
+ }
+ ;
+ window_definition:
+ IDENT AS window_specification
+ {
+ WinDef *n = (WinDef *) $3;
+ n->name = pstrdup($1);
+ $$ = (Node *) n;
+ }
+ ;
+
+ /*
* Supporting nonterminals for expressions.
*/
***************
*** 9463,9468 **** unreserved_keyword:
--- 9629,9635 ----
| ENCRYPTED
| ENUM_P
| ESCAPE
+ | EXCLUDE
| EXCLUDING
| EXCLUSIVE
| EXECUTE
***************
*** 9470,9475 **** unreserved_keyword:
--- 9637,9643 ----
| EXTERNAL
| FAMILY
| FIRST_P
+ | FOLLOWING
| FORCE
| FORWARD
| FUNCTION
***************
*** 9535,9546 **** unreserved_keyword:
--- 9703,9717 ----
| OIDS
| OPERATOR
| OPTION
+ | OTHERS
| OWNED
| OWNER
| PARSER
| PARTIAL
| PASSWORD
| PLANS
+ | PARTITION
+ | PRECEDING
| PREPARE
| PREPARED
| PRESERVE
***************
*** 9549,9554 **** unreserved_keyword:
--- 9720,9726 ----
| PROCEDURAL
| PROCEDURE
| QUOTE
+ | RANGE
| READ
| REASSIGN
| RECHECK
***************
*** 9600,9610 **** unreserved_keyword:
--- 9772,9784 ----
| TEMPLATE
| TEMPORARY
| TEXT_P
+ | TIES
| TRANSACTION
| TRIGGER
| TRUNCATE
| TRUSTED
| TYPE_P
+ | UNBOUNDED
| UNCOMMITTED
| UNENCRYPTED
| UNKNOWN
***************
*** 9785,9790 **** reserved_keyword:
--- 9959,9965 ----
| ONLY
| OR
| ORDER
+ | OVER
| PLACING
| PRIMARY
| REFERENCES
***************
*** 9805,9810 **** reserved_keyword:
--- 9980,9986 ----
| VARIADIC
| WHEN
| WHERE
+ | WINDOW
| WITH
;
*** a/src/backend/parser/keywords.c
--- b/src/backend/parser/keywords.c
***************
*** 160,165 **** const ScanKeyword ScanKeywords[] = {
--- 160,166 ----
{"enum", ENUM_P, UNRESERVED_KEYWORD},
{"escape", ESCAPE, UNRESERVED_KEYWORD},
{"except", EXCEPT, RESERVED_KEYWORD},
+ {"exclude", EXCLUDE, UNRESERVED_KEYWORD},
{"excluding", EXCLUDING, UNRESERVED_KEYWORD},
{"exclusive", EXCLUSIVE, UNRESERVED_KEYWORD},
{"execute", EXECUTE, UNRESERVED_KEYWORD},
***************
*** 172,177 **** const ScanKeyword ScanKeywords[] = {
--- 173,179 ----
{"fetch", FETCH, RESERVED_KEYWORD},
{"first", FIRST_P, UNRESERVED_KEYWORD},
{"float", FLOAT_P, COL_NAME_KEYWORD},
+ {"following", FOLLOWING, UNRESERVED_KEYWORD},
{"for", FOR, RESERVED_KEYWORD},
{"force", FORCE, UNRESERVED_KEYWORD},
{"foreign", FOREIGN, RESERVED_KEYWORD},
***************
*** 283,300 **** const ScanKeyword ScanKeywords[] = {
--- 285,306 ----
{"option", OPTION, UNRESERVED_KEYWORD},
{"or", OR, RESERVED_KEYWORD},
{"order", ORDER, RESERVED_KEYWORD},
+ {"others", OTHERS, UNRESERVED_KEYWORD},
{"out", OUT_P, COL_NAME_KEYWORD},
{"outer", OUTER_P, TYPE_FUNC_NAME_KEYWORD},
+ {"over", OVER, RESERVED_KEYWORD},
{"overlaps", OVERLAPS, TYPE_FUNC_NAME_KEYWORD},
{"overlay", OVERLAY, COL_NAME_KEYWORD},
{"owned", OWNED, UNRESERVED_KEYWORD},
{"owner", OWNER, UNRESERVED_KEYWORD},
{"parser", PARSER, UNRESERVED_KEYWORD},
{"partial", PARTIAL, UNRESERVED_KEYWORD},
+ {"partition", PARTITION, UNRESERVED_KEYWORD},
{"password", PASSWORD, UNRESERVED_KEYWORD},
{"placing", PLACING, RESERVED_KEYWORD},
{"plans", PLANS, UNRESERVED_KEYWORD},
{"position", POSITION, COL_NAME_KEYWORD},
+ {"preceding", PRECEDING, UNRESERVED_KEYWORD},
{"precision", PRECISION, COL_NAME_KEYWORD},
{"prepare", PREPARE, UNRESERVED_KEYWORD},
{"prepared", PREPARED, UNRESERVED_KEYWORD},
***************
*** 305,310 **** const ScanKeyword ScanKeywords[] = {
--- 311,317 ----
{"procedural", PROCEDURAL, UNRESERVED_KEYWORD},
{"procedure", PROCEDURE, UNRESERVED_KEYWORD},
{"quote", QUOTE, UNRESERVED_KEYWORD},
+ {"range", RANGE, UNRESERVED_KEYWORD},
{"read", READ, UNRESERVED_KEYWORD},
{"real", REAL, COL_NAME_KEYWORD},
{"reassign", REASSIGN, UNRESERVED_KEYWORD},
***************
*** 371,376 **** const ScanKeyword ScanKeywords[] = {
--- 378,384 ----
{"temporary", TEMPORARY, UNRESERVED_KEYWORD},
{"text", TEXT_P, UNRESERVED_KEYWORD},
{"then", THEN, RESERVED_KEYWORD},
+ {"ties", TIES, UNRESERVED_KEYWORD},
{"time", TIME, COL_NAME_KEYWORD},
{"timestamp", TIMESTAMP, COL_NAME_KEYWORD},
{"to", TO, RESERVED_KEYWORD},
***************
*** 383,388 **** const ScanKeyword ScanKeywords[] = {
--- 391,397 ----
{"truncate", TRUNCATE, UNRESERVED_KEYWORD},
{"trusted", TRUSTED, UNRESERVED_KEYWORD},
{"type", TYPE_P, UNRESERVED_KEYWORD},
+ {"unbounded", UNBOUNDED, UNRESERVED_KEYWORD},
{"uncommitted", UNCOMMITTED, UNRESERVED_KEYWORD},
{"unencrypted", UNENCRYPTED, UNRESERVED_KEYWORD},
{"union", UNION, RESERVED_KEYWORD},
***************
*** 408,413 **** const ScanKeyword ScanKeywords[] = {
--- 417,423 ----
{"when", WHEN, RESERVED_KEYWORD},
{"where", WHERE, RESERVED_KEYWORD},
{"whitespace", WHITESPACE_P, UNRESERVED_KEYWORD},
+ {"window", WINDOW, RESERVED_KEYWORD},
{"with", WITH, RESERVED_KEYWORD},
{"without", WITHOUT, UNRESERVED_KEYWORD},
{"work", WORK, UNRESERVED_KEYWORD},
*** a/src/backend/parser/parse_agg.c
--- b/src/backend/parser/parse_agg.c
***************
*** 1,7 ****
/*-------------------------------------------------------------------------
*
* parse_agg.c
! * handle aggregates in parser
*
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
--- 1,7 ----
/*-------------------------------------------------------------------------
*
* parse_agg.c
! * handle aggregates and window functions in parser
*
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
***************
*** 73,78 **** transformAggregateCall(ParseState *pstate, Aggref *agg)
--- 73,84 ----
errmsg("aggregate function calls cannot be nested"),
parser_errposition(pstate,
locate_agg_of_level((Node *) agg->args, 0))));
+ if (checkExprHasWFuncs((Node *) agg->args))
+ ereport(ERROR,
+ (errcode(ERRCODE_GROUPING_ERROR),
+ errmsg("aggregate function calls cannot take window functions as arguments"),
+ parser_errposition(pstate,
+ locate_agg_of_level((Node *) agg->args, 0))));
}
if (min_varlevel < 0)
***************
*** 85,90 **** transformAggregateCall(ParseState *pstate, Aggref *agg)
--- 91,130 ----
pstate->p_hasAggs = true;
}
+ /*
+ * transformWindowCall -
+ *
+ */
+ void
+ transformWindowCall(ParseState *pstate, WFunc *wfunc)
+ {
+ int min_varlevel;
+
+ /*
+ * The aggregate's level is the same as the level of the lowest-level
+ * variable or aggregate in its arguments; or if it contains no variables
+ * at all, we presume it to be local.
+ */
+ min_varlevel = find_minimum_var_level((Node *) wfunc->args);
+
+ /*
+ * An aggregate can't directly contain another aggregate call of the same
+ * level (though outer aggs are okay). We can skip this check if we
+ * didn't find any local vars or aggs.
+ */
+ if (min_varlevel == 0)
+ {
+ if (checkExprHasWFuncs((Node *) wfunc->args))
+ ereport(ERROR,
+ (errcode(ERRCODE_WINDOWING_ERROR),
+ errmsg("window function calls cannot be nested")));
+ }
+
+ if (min_varlevel < 0)
+ min_varlevel = 0;
+ wfunc->winlevelsup = min_varlevel;
+ pstate->p_hasWindow = true;
+ }
/*
* parseCheckAggregates
***************
*** 231,236 **** parseCheckAggregates(ParseState *pstate, Query *qry)
--- 271,311 ----
locate_agg_of_level((Node *) qry, 0))));
}
+ /*
+ * Window functions must not be in either WHERE, HAVING, or GRUP BY clauses.
+ */
+ void
+ parseCheckWindow(ParseState *pstate, Query *qry)
+ {
+ ListCell *l;
+
+ if (checkExprHasWFuncs(qry->jointree->quals))
+ ereport(ERROR,
+ (errcode(ERRCODE_WINDOWING_ERROR),
+ errmsg("window functions not allowed in WHERE clause")));
+ if (checkExprHasWFuncs((Node *) qry->jointree->fromlist))
+ ereport(ERROR,
+ (errcode(ERRCODE_WINDOWING_ERROR),
+ errmsg("window functions not allowed in JOIN conditions")));
+ if (checkExprHasWFuncs(qry->havingQual))
+ ereport(ERROR,
+ (errcode(ERRCODE_WINDOWING_ERROR),
+ errmsg("window functions not allowed in HAVING clause")));
+
+ foreach(l, qry->groupClause)
+ {
+ SortGroupClause *grpcl = (SortGroupClause *) lfirst(l);
+ Node *expr;
+
+ expr = get_sortgroupclause_expr(grpcl, qry->targetList);
+ if (expr == NULL)
+ continue; /* probably cannot happen */
+ if (checkExprHasWFuncs(expr))
+ ereport(ERROR,
+ (errcode(ERRCODE_WINDOWING_ERROR),
+ errmsg("window functions not allowed in GROUP BY clause")));
+ }
+ }
/*
* check_ungrouped_columns -
*** a/src/backend/parser/parse_clause.c
--- b/src/backend/parser/parse_clause.c
***************
*** 40,47 ****
#define ORDER_CLAUSE 0
#define GROUP_CLAUSE 1
#define DISTINCT_ON_CLAUSE 2
! static char *clauseText[] = {"ORDER BY", "GROUP BY", "DISTINCT ON"};
static void extractRemainingColumns(List *common_colnames,
List *src_colnames, List *src_colvars,
--- 40,49 ----
#define ORDER_CLAUSE 0
#define GROUP_CLAUSE 1
#define DISTINCT_ON_CLAUSE 2
+ #define PARTITION_CLAUSE 3
+ #define WIN_ORDER_CLAUSE 4
! static char *clauseText[] = {"ORDER BY", "GROUP BY", "DISTINCT ON", "PARTITION", "ORDER BY"};
static void extractRemainingColumns(List *common_colnames,
List *src_colnames, List *src_colvars,
***************
*** 68,73 **** static Node *buildMergedJoinVar(ParseState *pstate, JoinType jointype,
--- 70,77 ----
Var *l_colvar, Var *r_colvar);
static TargetEntry *findTargetlistEntry(ParseState *pstate, Node *node,
List **tlist, int clause);
+ static WindowClause *findWindowClause(List *wclist, const char *name,
+ List *partitionClause, List *orderClause);
static int get_matching_location(int sortgroupref,
List *sortgrouprefs, List *exprs);
static List *addTargetToSortList(ParseState *pstate, TargetEntry *tle,
***************
*** 565,570 **** transformRangeFunction(ParseState *pstate, RangeFunction *r)
--- 569,582 ----
locate_agg_of_level(funcexpr, 0))));
}
+ if (pstate->p_hasWindow)
+ {
+ if (checkExprHasWFuncs(funcexpr))
+ ereport(ERROR,
+ (errcode(ERRCODE_WINDOWING_ERROR),
+ errmsg("cannot use window function in function expression in FROM")));
+ }
+
/*
* OK, build an RTE for the function.
*/
***************
*** 1301,1306 **** findTargetlistEntry(ParseState *pstate, Node *node, List **tlist, int clause)
--- 1313,1343 ----
clauseText[clause]),
parser_errposition(pstate, location)));
+ /*
+ * In ORDER BY clause of a window, simple integer means
+ * integer data, not target pos.
+ */
+ if (clause == WIN_ORDER_CLAUSE)
+ {
+ TargetEntry *tle;
+ Const *cons;
+ AttrNumber resno;
+
+ resno = list_length(*tlist) + 1;
+ cons = makeConst(INT4OID,
+ -1,
+ sizeof(int32),
+ Int32GetDatum(intVal(val)),
+ false,
+ true);
+ tle = makeTargetEntry((Expr *) cons,
+ resno,
+ NULL,
+ true);
+ *tlist = lappend(*tlist, tle);
+ return tle;
+ }
+
target_pos = intVal(val);
foreach(tl, *tlist)
{
***************
*** 1452,1457 **** transformSortClause(ParseState *pstate,
--- 1489,1660 ----
}
/*
+ * transformOrderClause -
+ *
+ * OrderClause is a set of SortBys. Only tag type is different.
+ */
+ List *
+ transformOrderClause(ParseState *pstate,
+ List *orderlist,
+ List **targetlist,
+ bool resolveUnknown)
+ {
+ List *result = NIL;
+ ListCell *l;
+ TargetEntry *tle;
+
+ foreach(l, orderlist)
+ {
+ SortBy *sortby = lfirst(l);
+
+ tle = findTargetlistEntry(pstate, sortby->node,
+ targetlist, WIN_ORDER_CLAUSE);
+ result = addTargetToSortList(pstate, tle,
+ result, *targetlist,
+ sortby, resolveUnknown);
+ }
+
+ return result;
+ }
+
+ /*
+ * transformPartitionClause -
+ *
+ * Almost everything PartitionClause has is the same as GroupClause.
+ */
+ List *
+ transformPartitionClause(ParseState *pstate,
+ List *partitionlist,
+ List **targetlist)
+ {
+ List *result = NIL;
+ ListCell *l;
+ TargetEntry *tle;
+
+ foreach(l, partitionlist)
+ {
+ Oid restype;
+ Oid sortop;
+ Oid eqop;
+ PartitionClause *pc;
+
+ tle = findTargetlistEntry(pstate, lfirst(l), targetlist, PARTITION_CLAUSE);
+
+ restype = exprType((Node *) tle->expr);
+
+ if (restype == UNKNOWNOID)
+ tle->expr = (Expr *) coerce_type(pstate, (Node *) tle->expr,
+ restype, TEXTOID, -1,
+ COERCION_IMPLICIT,
+ COERCE_IMPLICIT_CAST,
+ -1);
+ pc = makeNode(PartitionClause);
+ pc->tleSortGroupRef = assignSortGroupRef(tle, *targetlist);
+ get_sort_group_operators(restype,
+ false, true, false,
+ &sortop, &eqop, NULL);
+ pc->eqop = eqop;
+ pc->sortop = sortop;
+ pc->nulls_first = false;
+ result = lappend(result, pc);
+ }
+
+ return result;
+ }
+
+ /*
+ * transformWinDef -
+ *
+ * PARTITION BY and ORDER BY clauses are transformed and WFuncs are tied with
+ * WindowClause here. During this process, WindowClause that has not window function
+ * (this case would happen when using WINDOW clause) is removed.
+ */
+ List *
+ transformWinDef(ParseState *pstate,
+ List *windefinition,
+ List **targetlist)
+ {
+ List *result = NIL, *window_clauses = NIL;
+ ListCell *l;
+ Index winref = 1;
+
+ foreach(l, windefinition)
+ {
+ WinDef *windef = (WinDef *) lfirst(l);
+ List *partitionClause = NIL;
+ List *orderClause = NIL;
+ WindowClause *wc;
+
+ partitionClause = transformPartitionClause(pstate,
+ windef->partitionClause,
+ targetlist);
+ orderClause = transformOrderClause(pstate,
+ windef->orderClause,
+ targetlist,
+ true);
+
+ /*
+ * If there is the same node that has been in the list,
+ * refer to it.
+ */
+ wc = findWindowClause(window_clauses, windef->name, partitionClause, orderClause);
+ if (!wc)
+ {
+ if (windef->name && windef->wfunc)
+ {
+ /*
+ * Though OVER clause uses window name, there's
+ * no definition in WINDOW clause.
+ */
+ ereport(ERROR,
+ (errcode(ERRCODE_WRONG_OBJECT_TYPE),
+ errmsg("window name(%s) is not found in WINDOW clause",
+ windef->name)));
+ }
+
+ wc = makeNode(WindowClause);
+ wc->partitionClause = partitionClause;
+ wc->orderClause = orderClause;
+ wc->name = windef->name;
+ wc->has_wfunc = false;
+ wc->winref = winref++;
+
+ window_clauses = lappend(window_clauses, wc);
+ }
+
+ /*
+ * Tie the function with the appropriate window
+ */
+ if (windef->wfunc)
+ {
+ windef->wfunc->winref = wc->winref;
+ wc->has_wfunc = true;
+ /*
+ * we now recognize Window operation will be needed.
+ */
+ pstate->p_hasWindow = true;
+ }
+ }
+
+ /*
+ * filter those which isn't tied with any functions
+ */
+ foreach(l, window_clauses)
+ {
+ WindowClause *wc = (WindowClause *) lfirst(l);
+
+ if (wc->has_wfunc)
+ result = lappend(result, wc);
+ else
+ pfree(wc);
+ }
+
+ list_free(window_clauses);
+
+ return result;
+ }
+
+ /*
* transformDistinctClause -
* transform a DISTINCT clause
*
***************
*** 1919,1921 **** targetIsInSortList(TargetEntry *tle, Oid sortop, List *sortList)
--- 2122,2152 ----
}
return false;
}
+
+ /*
+ * find_window_clause -
+ *
+ * search for the WindowClause which has already been in the list.
+ * It is done by name or by the set of partition and order.
+ */
+ static WindowClause *
+ findWindowClause(List *wclist, const char *name, List *partitionClause, List *orderClause)
+ {
+ ListCell *l;
+
+ foreach(l, wclist)
+ {
+ WindowClause *wc = (WindowClause *) lfirst(l);
+ if (wc->name && name)
+ {
+ if (strcmp(wc->name, name) == 0)
+ return wc;
+ }
+
+ if (equal(wc->partitionClause, partitionClause) &&
+ equal(wc->orderClause, orderClause))
+ return wc;
+ }
+
+ return NULL;
+ }
*** a/src/backend/parser/parse_expr.c
--- b/src/backend/parser/parse_expr.c
***************
*** 361,367 **** transformIndirection(ParseState *pstate, Node *basenode, List *indirection)
list_make1(n),
list_make1(result),
false, false, false,
! true, -1);
}
}
/* process trailing subscripts, if any */
--- 361,367 ----
list_make1(n),
list_make1(result),
false, false, false,
! true, NULL, -1);
}
}
/* process trailing subscripts, if any */
***************
*** 505,511 **** transformColumnRef(ParseState *pstate, ColumnRef *cref)
list_make1(makeString(name2)),
list_make1(node),
false, false, false,
! true, cref->location);
}
break;
}
--- 505,511 ----
list_make1(makeString(name2)),
list_make1(node),
false, false, false,
! true, NULL, cref->location);
}
break;
}
***************
*** 546,552 **** transformColumnRef(ParseState *pstate, ColumnRef *cref)
list_make1(makeString(name3)),
list_make1(node),
false, false, false,
! true, cref->location);
}
break;
}
--- 546,552 ----
list_make1(makeString(name3)),
list_make1(node),
false, false, false,
! true, NULL, cref->location);
}
break;
}
***************
*** 601,607 **** transformColumnRef(ParseState *pstate, ColumnRef *cref)
list_make1(makeString(name4)),
list_make1(node),
false, false, false,
! true, cref->location);
}
break;
}
--- 601,607 ----
list_make1(makeString(name4)),
list_make1(node),
false, false, false,
! true, NULL, cref->location);
}
break;
}
***************
*** 1109,1114 **** transformFuncCall(ParseState *pstate, FuncCall *fn)
--- 1109,1115 ----
fn->agg_distinct,
fn->func_variadic,
false,
+ fn->win_definition,
fn->location);
}
*** a/src/backend/parser/parse_func.c
--- b/src/backend/parser/parse_func.c
***************
*** 15,20 ****
--- 15,21 ----
#include "postgres.h"
#include "access/heapam.h"
+ #include "catalog/pg_aggregate.h"
#include "catalog/pg_inherits.h"
#include "catalog/pg_proc.h"
#include "catalog/pg_type.h"
***************
*** 63,69 **** static void unknown_attribute(ParseState *pstate, Node *relref, char *attname,
Node *
ParseFuncOrColumn(ParseState *pstate, List *funcname, List *fargs,
bool agg_star, bool agg_distinct, bool func_variadic,
! bool is_column, int location)
{
Oid rettype;
Oid funcid;
--- 64,70 ----
Node *
ParseFuncOrColumn(ParseState *pstate, List *funcname, List *fargs,
bool agg_star, bool agg_distinct, bool func_variadic,
! bool is_column, WinDef *windef, int location)
{
Oid rettype;
Oid funcid;
***************
*** 76,81 **** ParseFuncOrColumn(ParseState *pstate, List *funcname, List *fargs,
--- 77,84 ----
Node *retval;
bool retset;
int nvargs;
+ bool isagg;
+ bool iswfunc;
FuncDetailCode fdresult;
/*
***************
*** 164,169 **** ParseFuncOrColumn(ParseState *pstate, List *funcname, List *fargs,
--- 167,173 ----
fdresult = func_get_detail(funcname, fargs, nargs, actual_arg_types,
!func_variadic,
&funcid, &rettype, &retset, &nvargs,
+ &isagg, &iswfunc,
&declared_arg_types);
if (fdresult == FUNCDETAIL_COERCION)
{
***************
*** 195,201 **** ParseFuncOrColumn(ParseState *pstate, List *funcname, List *fargs,
NameListToString(funcname)),
parser_errposition(pstate, location)));
}
! else if (fdresult != FUNCDETAIL_AGGREGATE)
{
/*
* Oops. Time to die.
--- 199,205 ----
NameListToString(funcname)),
parser_errposition(pstate, location)));
}
! else if (fdresult != FUNCDETAIL_AGG_OR_WFUNC)
{
/*
* Oops. Time to die.
***************
*** 291,330 **** ParseFuncOrColumn(ParseState *pstate, List *funcname, List *fargs,
funcexpr->location = location;
retval = (Node *) funcexpr;
}
else
{
! /* aggregate function */
! Aggref *aggref = makeNode(Aggref);
! aggref->aggfnoid = funcid;
! aggref->aggtype = rettype;
! aggref->args = fargs;
! aggref->aggstar = agg_star;
! aggref->aggdistinct = agg_distinct;
! aggref->location = location;
! /*
! * Reject attempt to call a parameterless aggregate without (*)
! * syntax. This is mere pedantry but some folks insisted ...
! */
! if (fargs == NIL && !agg_star)
! ereport(ERROR,
! (errcode(ERRCODE_WRONG_OBJECT_TYPE),
! errmsg("%s(*) must be used to call a parameterless aggregate function",
! NameListToString(funcname)),
! parser_errposition(pstate, location)));
! /* parse_agg.c does additional aggregate-specific processing */
! transformAggregateCall(pstate, aggref);
! retval = (Node *) aggref;
! if (retset)
! ereport(ERROR,
! (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
! errmsg("aggregates cannot return sets"),
! parser_errposition(pstate, location)));
}
return retval;
--- 295,404 ----
funcexpr->location = location;
retval = (Node *) funcexpr;
+
+ if (windef)
+ ereport(ERROR,
+ (errcode(ERRCODE_WRONG_OBJECT_TYPE),
+ errmsg("%s is not a window function nor an aggregate function",
+ NameListToString(funcname)),
+ parser_errposition(pstate, location)));
}
else
{
! Assert(fdresult == FUNCDETAIL_AGG_OR_WFUNC);
! if (isagg && !windef)
! {
! /* aggregate function */
! Aggref *aggref = makeNode(Aggref);
! aggref->aggfnoid = funcid;
! aggref->aggtype = rettype;
! aggref->args = fargs;
! aggref->aggstar = agg_star;
! aggref->aggdistinct = agg_distinct;
! aggref->location = location;
! /*
! * Reject attempt to call a parameterless aggregate without (*)
! * syntax. This is mere pedantry but some folks insisted ...
! */
! if (fargs == NIL && !agg_star)
! ereport(ERROR,
! (errcode(ERRCODE_WRONG_OBJECT_TYPE),
! errmsg("%s(*) must be used to call a parameterless aggregate function",
! NameListToString(funcname)),
! parser_errposition(pstate, location)));
!
! /* parse_agg.c does additional aggregate-specific processing */
! transformAggregateCall(pstate, aggref);
!
! retval = (Node *) aggref;
!
! if (retset)
! ereport(ERROR,
! (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
! errmsg("aggregates cannot return sets"),
! parser_errposition(pstate, location)));
! }
! else
! {
! /* window function */
! WFunc *wfunc = makeNode(WFunc);
!
! /*
! * Window functions must be called with window definition.
! */
! if (!windef)
! ereport(ERROR,
! (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
! errmsg("window function call need window definition"),
! parser_errposition(pstate, location)));
! /*
! * normal aggregate can be called as window function by
! * the special aggregate wrapper function. By using wrappepr,
! * the performance is dropped but result is same.
! */
! if (isagg && !iswfunc)
! wfunc->pure_agg = true;
! wfunc->winfnoid = funcid;
! wfunc->wintype = rettype;
! wfunc->args = fargs;
! wfunc->location = location;
! /*
! * agg_star is acceptable for aggregate functions
! * but distinct sould be rejected in parser though checked here again.
! */
! wfunc->winstar = agg_star;
! if (agg_distinct)
! ereport(ERROR,
! (errcode(ERRCODE_SYNTAX_ERROR),
! errmsg("windowing functions cannot accept DISTINCT argument.")));
! /*
! * Reject attempt to call a parameterless aggregate without (*)
! * syntax. This is mere pedantry but some folks insisted ...
! */
! if (wfunc->pure_agg && fargs == NIL && !agg_star)
! ereport(ERROR,
! (errcode(ERRCODE_WRONG_OBJECT_TYPE),
! errmsg("%s(*) must be used to call a parameterless aggregate function",
! NameListToString(funcname)),
! parser_errposition(pstate, location)));
! transformWindowCall(pstate, wfunc);
!
! retval = (Node *) wfunc;
!
! pstate->p_windef_list = lappend(pstate->p_windef_list, windef);
! windef->wfunc = wfunc;
!
! if (retset)
! ereport(ERROR,
! (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
! errmsg("window functions cannot return sets"),
! parser_errposition(pstate, location)));
! }
}
return retval;
***************
*** 729,734 **** func_get_detail(List *funcname,
--- 803,810 ----
Oid *rettype, /* return value */
bool *retset, /* return value */
int *nvargs, /* return value */
+ bool *isagg, /* return value */
+ bool *iswfunc, /* return value */
Oid **true_typeids) /* return value */
{
FuncCandidateList raw_candidates;
***************
*** 880,886 **** func_get_detail(List *funcname,
pform = (Form_pg_proc) GETSTRUCT(ftup);
*rettype = pform->prorettype;
*retset = pform->proretset;
! result = pform->proisagg ? FUNCDETAIL_AGGREGATE : FUNCDETAIL_NORMAL;
ReleaseSysCache(ftup);
return result;
}
--- 956,972 ----
pform = (Form_pg_proc) GETSTRUCT(ftup);
*rettype = pform->prorettype;
*retset = pform->proretset;
! *isagg = pform->proisagg;
! *iswfunc = pform->proiswfunc;
! /*
! * agg and wfunc are similar to each other
! * and overlaps as well. So we return agg_or_wfunc then
! * delegate to caller the detail process depending on which.
! */
! if (pform->proisagg || pform->proiswfunc)
! result = FUNCDETAIL_AGG_OR_WFUNC;
! else
! result = FUNCDETAIL_NORMAL;
ReleaseSysCache(ftup);
return result;
}
***************
*** 1374,1376 **** LookupAggNameTypeNames(List *aggname, List *argtypes, bool noError)
--- 1460,1465 ----
return oid;
}
+
+
+
*** a/src/backend/rewrite/rewriteManip.c
--- b/src/backend/rewrite/rewriteManip.c
***************
*** 36,41 **** typedef struct
--- 36,43 ----
static bool contain_aggs_of_level_walker(Node *node,
contain_aggs_of_level_context *context);
+ static bool checkExprHasWFuncs_walker(Node *node,
+ contain_aggs_of_level_context *context);
static bool locate_agg_of_level_walker(Node *node,
locate_agg_of_level_context *context);
static bool checkExprHasSubLink_walker(Node *node, void *context);
***************
*** 110,115 **** contain_aggs_of_level_walker(Node *node,
--- 112,161 ----
(void *) context);
}
+ bool
+ checkExprHasWFuncs(Node *node)
+ {
+ contain_aggs_of_level_context context;
+
+ context.sublevels_up = 0;
+
+ /*
+ * Must be prepared to start with a Query or a bare expression tree; if
+ * it's a Query, we don't want to increment sublevels_up.
+ */
+ return query_or_expression_tree_walker(node,
+ checkExprHasWFuncs_walker,
+ (void *) &context,
+ 0);
+ }
+
+ static bool
+ checkExprHasWFuncs_walker(Node *node, contain_aggs_of_level_context *context)
+ {
+ if (node == NULL)
+ return false;
+ if (IsA(node, WFunc))
+ {
+ if (((WFunc *) node)->winlevelsup == context->sublevels_up)
+ return true; /* abort the tree traversal and return true */
+ /* else fall through to examine argument */
+ }
+ if (IsA(node, Query))
+ {
+ /* Recurse into subselects */
+ bool result;
+
+ context->sublevels_up++;
+ result = query_tree_walker((Query *) node,
+ checkExprHasWFuncs_walker,
+ (void *) context, 0);
+ context->sublevels_up--;
+ return result;
+ }
+ return expression_tree_walker(node, checkExprHasWFuncs_walker,
+ (void *) context);
+ }
+
/*
* locate_agg_of_level -
* Find the parse location of any aggregate of the specified query level.
*** a/src/backend/utils/adt/Makefile
--- b/src/backend/utils/adt/Makefile
***************
*** 29,35 **** OBJS = acl.o arrayfuncs.o array_userfuncs.o arrayutils.o bool.o \
tsginidx.o tsgistidx.o tsquery.o tsquery_cleanup.o tsquery_gist.o \
tsquery_op.o tsquery_rewrite.o tsquery_util.o tsrank.o \
tsvector.o tsvector_op.o tsvector_parser.o \
! txid.o uuid.o xml.o
like.o: like.c like_match.c
--- 29,35 ----
tsginidx.o tsgistidx.o tsquery.o tsquery_cleanup.o tsquery_gist.o \
tsquery_op.o tsquery_rewrite.o tsquery_util.o tsrank.o \
tsvector.o tsvector_op.o tsvector_parser.o \
! txid.o uuid.o wfunc.o xml.o
like.o: like.c like_match.c
*** a/src/backend/utils/adt/ruleutils.c
--- b/src/backend/utils/adt/ruleutils.c
***************
*** 183,188 **** static void get_oper_expr(OpExpr *expr, deparse_context *context);
--- 183,189 ----
static void get_func_expr(FuncExpr *expr, deparse_context *context,
bool showimplicit);
static void get_agg_expr(Aggref *aggref, deparse_context *context);
+ static void get_wfunc_expr(WFunc *wfunc, deparse_context *context);
static void get_coercion_expr(Node *arg, deparse_context *context,
Oid resulttype, int32 resulttypmod,
Node *parentNode);
***************
*** 4014,4019 **** get_rule_expr(Node *node, deparse_context *context,
--- 4015,4024 ----
get_agg_expr((Aggref *) node, context);
break;
+ case T_WFunc:
+ get_wfunc_expr((WFunc *) node, context);
+ break;
+
case T_ArrayRef:
{
ArrayRef *aref = (ArrayRef *) node;
***************
*** 4972,4977 **** get_agg_expr(Aggref *aggref, deparse_context *context)
--- 4977,5015 ----
appendStringInfoChar(buf, ')');
}
+ /*
+ * get_wfunc_expr - Parse back an WFunc node
+ */
+ static void
+ get_wfunc_expr(WFunc *wfunc, deparse_context *context)
+ {
+ StringInfo buf = context->buf;
+ Oid argtypes[FUNC_MAX_ARGS];
+ int nargs;
+ ListCell *l;
+
+ nargs = 0;
+ foreach(l, wfunc->args)
+ {
+ if (nargs >= FUNC_MAX_ARGS)
+ ereport(ERROR,
+ (errcode(ERRCODE_TOO_MANY_ARGUMENTS),
+ errmsg("too many arguments")));
+ argtypes[nargs] = exprType((Node *) lfirst(l));
+ nargs++;
+ }
+
+ appendStringInfo(buf, "%s(%s",
+ generate_function_name(wfunc->winfnoid,
+ nargs, argtypes, NULL), "");
+ /* winstar can be set only in zero-argument aggregates */
+ if (wfunc->winstar)
+ appendStringInfoChar(buf, '*');
+ else
+ get_rule_expr((Node *) wfunc->args, context, true);
+ appendStringInfoChar(buf, ')');
+ }
+
/* ----------
* get_coercion_expr
*
***************
*** 5983,5988 **** generate_function_name(Oid funcid, int nargs, Oid *argtypes,
--- 6021,6028 ----
Oid p_rettype;
bool p_retset;
int p_nvargs;
+ bool p_isagg;
+ bool p_iswfunc;
Oid *p_true_typeids;
proctup = SearchSysCache(PROCOID,
***************
*** 6002,6009 **** generate_function_name(Oid funcid, int nargs, Oid *argtypes,
p_result = func_get_detail(list_make1(makeString(proname)),
NIL, nargs, argtypes, false,
&p_funcid, &p_rettype,
! &p_retset, &p_nvargs, &p_true_typeids);
! if ((p_result == FUNCDETAIL_NORMAL || p_result == FUNCDETAIL_AGGREGATE) &&
p_funcid == funcid)
nspname = NULL;
else
--- 6042,6050 ----
p_result = func_get_detail(list_make1(makeString(proname)),
NIL, nargs, argtypes, false,
&p_funcid, &p_rettype,
! &p_retset, &p_nvargs,
! &p_isagg, &p_iswfunc, &p_true_typeids);
! if ((p_result == FUNCDETAIL_NORMAL || p_result == FUNCDETAIL_AGG_OR_WFUNC) &&
p_funcid == funcid)
nspname = NULL;
else
*** /dev/null
--- b/src/backend/utils/adt/wfunc.c
***************
*** 0 ****
--- 1,492 ----
+ /*-------------------------------------------------------------------------
+ *
+ * wfunc.c
+ * Builtin window functions defined in SQL spec.
+ *
+ * Portions Copyright (c) 2000-2008, PostgreSQL Global Development Group
+ *
+ *
+ * IDENTIFICATION
+ * $PostgreSQL$
+ *
+ *-------------------------------------------------------------------------
+ */
+
+ #include "postgres.h"
+ #include "executor/executor.h"
+ #include "executor/nodeWindow.h"
+ #include "utils/builtins.h"
+
+ static bool rank_up(FunctionCallInfo fcinfo);
+ static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool fetchdefault);
+
+ /*
+ * SQL spec window functions
+ */
+ Datum row_number(PG_FUNCTION_ARGS);
+ Datum rank(PG_FUNCTION_ARGS);
+ Datum dense_rank(PG_FUNCTION_ARGS);
+ Datum percent_rank(PG_FUNCTION_ARGS);
+ Datum cume_dist(PG_FUNCTION_ARGS);
+ Datum ntile(PG_FUNCTION_ARGS);
+ Datum lag(PG_FUNCTION_ARGS);
+ Datum lag_withdefault(PG_FUNCTION_ARGS);
+ Datum lead(PG_FUNCTION_ARGS);
+ Datum lead_withdefault(PG_FUNCTION_ARGS);
+ Datum first_value(PG_FUNCTION_ARGS);
+ Datum last_value(PG_FUNCTION_ARGS);
+ Datum nth_value(PG_FUNCTION_ARGS);
+
+
+ /*
+ * ranking process information
+ */
+ typedef struct rank_context
+ {
+ int64 rank; /* current rank */
+ HeapTuple htup; /* row data one before the current */
+ } rank_context;
+
+ /*
+ * ntile process information
+ */
+ typedef struct
+ {
+ int32 ntile; /* current result */
+ int64 rows_per_bucket; /* row number of current bucket */
+ int64 boundary; /* how many rows should be in the bucket */
+ int64 remainder; /* (total rows) % (bucket num) */
+ } ntile_context;
+
+
+ /*
+ * allocate new user space for the bran new function call.
+ */
+ #define allocate_if_new(fcinfo, size) do{ \
+ if ((fcinfo)->flinfo->fn_extra == NULL) \
+ { \
+ MemoryContext __oldContext; \
+ __oldContext = MemoryContextSwitchTo((fcinfo)->flinfo->fn_mcxt); \
+ (fcinfo)->flinfo->fn_extra = palloc0(size); \
+ MemoryContextSwitchTo(__oldContext); \
+ } \
+ }while(0)
+
+ /*
+ * utility routine for *_rank functions.
+ */
+ static bool
+ rank_up(FunctionCallInfo fcinfo)
+ {
+ WindowObject winobj = PG_WINDOW_OBJECT();
+ WindowState *winstate;
+ Window *node;
+ TupleTableSlot *scanslot;
+ TupleTableSlot *winslot;
+ rank_context *context;
+ bool up = false; /* should rank up? */
+ bool res;
+ MemoryContext oldContext;
+
+ allocate_if_new(fcinfo, sizeof(rank_context));
+
+ winstate = (WindowState *) fcinfo->context;
+ node = (Window *) winstate->ss.ps.plan;
+ context = (rank_context *) fcinfo->flinfo->fn_extra;
+ winslot = winstate->tmpcontext->ecxt_outertuple;
+
+ if (context->rank == 0)
+ {
+ /* first call */
+ context->rank = 1;
+ res = WinRowGetTuple(winobj, winslot);
+ Assert(res);
+
+ oldContext = MemoryContextSwitchTo(fcinfo->flinfo->fn_mcxt);
+ context->htup = ExecCopySlotTuple(winslot);
+ MemoryContextSwitchTo(oldContext);
+
+ if (!node->ordNumCols)
+ elog(ERROR, "this function requires ORDER BY clause in the window");
+ }
+ else
+ {
+ /* we need two tuple slot to compare */
+ scanslot = winstate->ss.ss_ScanTupleSlot;
+
+ res = WinRowGetTuple(winobj, scanslot);
+ Assert(res);
+ ExecStoreTuple(context->htup, winslot, InvalidBuffer, false);
+
+ /* tuples matching by ORDER BY clause */
+ if (!WinRowIsPeer(winobj, scanslot, winslot))
+ {
+ heap_freetuple(context->htup);
+ oldContext = MemoryContextSwitchTo(fcinfo->flinfo->fn_mcxt);
+ context->htup = ExecCopySlotTuple(scanslot);
+ MemoryContextSwitchTo(oldContext);
+ up = true;
+ }
+ }
+
+ return up;
+ }
+
+
+ /*
+ * row_number
+ * just increment up from 1 until current partition finishes.
+ */
+ Datum
+ row_number(PG_FUNCTION_ARGS)
+ {
+ WindowObject winobj = PG_WINDOW_OBJECT();
+
+ PG_RETURN_INT64(WinRowCurrentPos(winobj) + 1);
+ }
+
+
+ /*
+ * rank
+ * increment up if key tuple changes. The new rank number is as the current row number.
+ */
+ Datum
+ rank(PG_FUNCTION_ARGS)
+ {
+ WindowObject winobj = PG_WINDOW_OBJECT();
+ rank_context *context;
+ bool up;
+
+ up = rank_up(fcinfo);
+ context = (rank_context *) fcinfo->flinfo->fn_extra;
+ if (up)
+ {
+ context->rank = WinRowCurrentPos(winobj) + 1;
+ }
+
+ PG_RETURN_INT64(context->rank);
+ }
+
+ /*
+ * dense_rank
+ * increment up if key tuple changes. The new rank number is as added up 1.
+ */
+ Datum
+ dense_rank(PG_FUNCTION_ARGS)
+ {
+ rank_context *context;
+ bool up;
+
+ up = rank_up(fcinfo);
+ context = (rank_context *) fcinfo->flinfo->fn_extra;
+ if (up)
+ {
+ context->rank += 1;
+ }
+
+ PG_RETURN_INT64(context->rank);
+ }
+
+ /*
+ * percent_rank
+ * return fraction between 0 and 1 inclusive, which
+ * is described as (RK - 1) / (NR - 1), where RK is the rank and NR is
+ * the number of total row, per spec.
+ */
+ Datum
+ percent_rank(PG_FUNCTION_ARGS)
+ {
+ WindowObject winobj = PG_WINDOW_OBJECT();
+ rank_context *context;
+ bool up;
+ int64 totalrow;
+
+ up = rank_up(fcinfo);
+ context = (rank_context *) fcinfo->flinfo->fn_extra;
+ if (up)
+ {
+ context->rank = WinRowCurrentPos(winobj) + 1;
+ }
+
+ totalrow = WinPartGetRowNum(winobj);
+ Assert(totalrow > 0);
+
+ /* result is as the first row, per spec */
+ if (totalrow == 1)
+ PG_RETURN_FLOAT8(0.0);
+
+ PG_RETURN_FLOAT8((float8) (context->rank - 1) / (float8) (totalrow - 1));
+ }
+
+ /*
+ * cume_dist
+ * return fraction betweeen 0 and 1 inclusive, which
+ * is described as NP / NR, where NP is the number of row preceeding or peers to
+ * the current row, and NR is the number of total row of the partition, per spec.
+ */
+ Datum
+ cume_dist(PG_FUNCTION_ARGS)
+ {
+ WindowObject winobj = PG_WINDOW_OBJECT();
+ rank_context *context;
+ bool up;
+ int64 totalrow;
+
+ up = rank_up(fcinfo);
+ context = (rank_context *) fcinfo->flinfo->fn_extra;
+ if (up || context->rank == 1)
+ {
+ /*
+ * The saved row is not peer to the current row or just the first,
+ * so count up the number of rows that are peer to the current.
+ */
+ WindowState *winstate = (WindowState *) fcinfo->context;
+ WindowIter iter;
+ TupleTableSlot *scanslot;
+ TupleTableSlot *winslot;
+
+ context->rank = WinRowCurrentPos(winobj) + 1;
+ scanslot = winstate->ss.ss_ScanTupleSlot;
+ winslot = winstate->tmpcontext->ecxt_outertuple;
+ ExecStoreTuple(context->htup, scanslot, InvalidBuffer, false);
+
+ /*
+ * start from current + 1
+ */
+ iter = WinPartStartIter(winobj, context->rank);
+ while(WinIterNext(iter))
+ {
+ if (!WinIterGetTuple(iter, winslot))
+ elog(ERROR, "failed fetch row");
+
+ if (!WinRowIsPeer(winobj, scanslot, winslot))
+ break;
+ context->rank++;
+ }
+ WinIterFinish(iter);
+ }
+
+ totalrow = WinPartGetRowNum(winobj);
+ Assert(totalrow > 0);
+
+ PG_RETURN_FLOAT8((float8) (context->rank) / (float8) totalrow);
+ }
+
+ /*
+ * ntile
+ * compute an exact numeric value with scale0 (zero),
+ * ranging from 1 (one) to n, per spec.
+ */
+ Datum
+ ntile(PG_FUNCTION_ARGS)
+ {
+ WindowObject winobj = PG_WINDOW_OBJECT();
+ ntile_context *context;
+
+ allocate_if_new(fcinfo, sizeof(ntile_context));
+
+ context = (ntile_context *) fcinfo->flinfo->fn_extra;
+
+ if (context->ntile == 0)
+ {
+ /* first call */
+ int64 total;
+ int32 nbuckets;
+ bool isnull;
+
+ total = WinPartGetRowNum(winobj);
+ nbuckets = WinRowGetArg(winobj, PG_WINDOW_ARG(0), &isnull);
+
+ /* window functions cannot be strict, so raise error */
+ if (isnull)
+ elog(ERROR, "null bucket number");
+
+ context->ntile = 1;
+ context->rows_per_bucket = 0;
+ context->boundary = total / nbuckets;
+ if (context->boundary <= 0)
+ context->boundary = 1;
+ else
+ {
+ /*
+ * If the total number is not divisible, add 1 row to
+ * leading buckets.
+ */
+ context->remainder = total % nbuckets;
+ if (context->remainder != 0)
+ context->boundary++;
+ }
+ }
+
+ context->rows_per_bucket++;
+ if (context->boundary < context->rows_per_bucket)
+ {
+ /* ntile up */
+ if (context->remainder != 0 && context->ntile == context->remainder)
+ {
+ context->remainder = 0;
+ context->boundary -= 1;
+ }
+ context->ntile += 1;
+ context->rows_per_bucket = 1;
+ }
+
+ PG_RETURN_INT32(context->ntile);
+ }
+
+ /*
+ * leadlag_common
+ * common operation of lead() and lag()
+ * for lead() forward argument is set to true, whereas lag() is to false,
+ * and if fetchdefault is true, the third argument is taken if the target
+ * datum is out of range.
+ */
+ static Datum
+ leadlag_common(FunctionCallInfo fcinfo, bool forward, bool fetchdefault)
+ {
+ WindowObject winobj = PG_WINDOW_OBJECT();
+ int4 offset;
+ Datum result;
+ bool isnull;
+ bool isout;
+
+ offset = WinRowGetArg(winobj, PG_WINDOW_ARG(1), &isnull);
+ if (isnull)
+ PG_RETURN_NULL();
+
+ result = WinPartGetArg(winobj, PG_WINDOW_ARG(0),
+ (forward ? offset : -offset),
+ WINDOW_SEEK_CURRENT, &isnull, &isout);
+
+ if (isout)
+ {
+ /*
+ * target row is out of the partition, so going to fetch
+ * default value if demanded.
+ */
+ if (fetchdefault)
+ result = WinRowGetArg(winobj, PG_WINDOW_ARG(2), &isnull);
+ }
+
+ if (isnull)
+ PG_RETURN_NULL();
+
+ PG_RETURN_DATUM(result);
+ }
+
+ /*
+ * lag
+ * returns the value of VE evaluated on a row that is OFFSET
+ * number of rows before the current row within a partition,
+ * per spec.
+ */
+ Datum
+ lag(PG_FUNCTION_ARGS)
+ {
+ return leadlag_common(fcinfo, false, false);
+ }
+
+ /*
+ * lag_withdefault
+ * same as lag but accepts default value as its third argument
+ */
+ Datum
+ lag_withdefault(PG_FUNCTION_ARGS)
+ {
+ return leadlag_common(fcinfo, false, true);
+ }
+
+ /*
+ * lead
+ * returns the value of VE evaluated on a row that is OFFSET
+ * number of rows after the current row within a partition,
+ * per spec.
+ */
+ Datum
+ lead(PG_FUNCTION_ARGS)
+ {
+ return leadlag_common(fcinfo, true, false);
+ }
+
+ /*
+ * lead_withdefault
+ * same as lead but accepts default value as its third argument
+ */
+ Datum
+ lead_withdefault(PG_FUNCTION_ARGS)
+ {
+ return leadlag_common(fcinfo, true, true);
+ }
+
+ /*
+ * first_value
+ * return the value of VE evaluated on the first row of the
+ * window frame, per spec.
+ */
+ Datum
+ first_value(PG_FUNCTION_ARGS)
+ {
+ WindowObject winobj = PG_WINDOW_OBJECT();
+ Datum result;
+ bool isnull;
+ bool isout;
+
+ result = WinFrameGetArg(winobj, PG_WINDOW_ARG(0),
+ 0, WINDOW_SEEK_HEAD, &isnull, &isout);
+
+ if (isnull)
+ PG_RETURN_NULL();
+
+ PG_RETURN_DATUM(result);
+ }
+
+ /*
+ * last_value
+ * return the value of VE evaluated on the last row of the
+ * window frame, per spec.
+ */
+ Datum
+ last_value(PG_FUNCTION_ARGS)
+ {
+ WindowObject winobj = PG_WINDOW_OBJECT();
+ Datum result;
+ bool isnull;
+ bool isout;
+
+ result = WinFrameGetArg(winobj, PG_WINDOW_ARG(0),
+ 0, WINDOW_SEEK_TAIL, &isnull, &isout);
+
+ if (isnull)
+ PG_RETURN_NULL();
+
+ PG_RETURN_DATUM(result);
+ }
+
+ /*
+ * nth_value
+ * return the value of VE evaluated on the n-th row from the first
+ * row of the window frame, per spec.
+ * The argument "nth" is an exact numeric value n with scale 0 (zero).
+ */
+ Datum
+ nth_value(PG_FUNCTION_ARGS)
+ {
+ WindowObject winobj = PG_WINDOW_OBJECT();
+ Datum result;
+ bool isnull;
+ bool isout;
+ int4 nth;
+
+ nth = WinRowGetArg(winobj, PG_WINDOW_ARG(1), &isnull);
+
+ if (isnull)
+ elog(ERROR, "nth value is null");
+
+ result = WinFrameGetArg(winobj, PG_WINDOW_ARG(0),
+ nth, WINDOW_SEEK_HEAD, &isnull, &isout);
+
+ if (isnull)
+ PG_RETURN_NULL();
+
+ PG_RETURN_DATUM(result);
+ }
*** a/src/backend/utils/sort/tuplestore.c
--- b/src/backend/utils/sort/tuplestore.c
***************
*** 1052,1057 **** tuplestore_copy_read_pointer(Tuplestorestate *state,
--- 1052,1087 ----
}
/*
+ * copy write pointer to the specified read pointer
+ */
+ void
+ tuplestore_write_to_read_pointer(Tuplestorestate *state, int readptr)
+ {
+ TSReadPointer *ptr = &state->readptrs[readptr];
+
+ Assert(readptr >= 0 && readptr < state->readptrcount);
+
+ switch(state->status)
+ {
+ case TSS_INMEM:
+ ptr->current = state->memtupcount;
+ break;
+ case TSS_WRITEFILE:
+ BufFileTell(state->myfile,
+ &ptr->file,
+ &ptr->offset);
+ break;
+ case TSS_READFILE:
+ ptr->file = state->writepos_file;
+ ptr->offset = state->writepos_offset;
+ break;
+ default:
+ elog(ERROR, "invalid tuplestore state");
+ break;
+ }
+ }
+
+ /*
* tuplestore_trim - remove all no-longer-needed tuples
*/
static void
*** a/src/include/catalog/pg_attribute.h
--- b/src/include/catalog/pg_attribute.h
***************
*** 295,314 **** DATA(insert ( 1247 tableoid 26 0 4 -7 0 -1 -1 t p i t f f t 0));
{ 1255, {"prorows"}, 700, -1, 4, 6, 0, -1, -1, FLOAT4PASSBYVAL, 'p', 'i', true, false, false, true, 0 }, \
{ 1255, {"provariadic"}, 26, -1, 4, 7, 0, -1, -1, true, 'p', 'i', true, false, false, true, 0 }, \
{ 1255, {"proisagg"}, 16, -1, 1, 8, 0, -1, -1, true, 'p', 'c', true, false, false, true, 0 }, \
! { 1255, {"prosecdef"}, 16, -1, 1, 9, 0, -1, -1, true, 'p', 'c', true, false, false, true, 0 }, \
! { 1255, {"proisstrict"}, 16, -1, 1, 10, 0, -1, -1, true, 'p', 'c', true, false, false, true, 0 }, \
! { 1255, {"proretset"}, 16, -1, 1, 11, 0, -1, -1, true, 'p', 'c', true, false, false, true, 0 }, \
! { 1255, {"provolatile"}, 18, -1, 1, 12, 0, -1, -1, true, 'p', 'c', true, false, false, true, 0 }, \
! { 1255, {"pronargs"}, 21, -1, 2, 13, 0, -1, -1, true, 'p', 's', true, false, false, true, 0 }, \
! { 1255, {"prorettype"}, 26, -1, 4, 14, 0, -1, -1, true, 'p', 'i', true, false, false, true, 0 }, \
! { 1255, {"proargtypes"}, 30, -1, -1, 15, 1, -1, -1, false, 'p', 'i', true, false, false, true, 0 }, \
! { 1255, {"proallargtypes"}, 1028, -1, -1, 16, 1, -1, -1, false, 'x', 'i', false, false, false, true, 0 }, \
! { 1255, {"proargmodes"}, 1002, -1, -1, 17, 1, -1, -1, false, 'x', 'i', false, false, false, true, 0 }, \
! { 1255, {"proargnames"}, 1009, -1, -1, 18, 1, -1, -1, false, 'x', 'i', false, false, false, true, 0 }, \
! { 1255, {"prosrc"}, 25, -1, -1, 19, 0, -1, -1, false, 'x', 'i', false, false, false, true, 0 }, \
! { 1255, {"probin"}, 17, -1, -1, 20, 0, -1, -1, false, 'x', 'i', false, false, false, true, 0 }, \
! { 1255, {"proconfig"}, 1009, -1, -1, 21, 1, -1, -1, false, 'x', 'i', false, false, false, true, 0 }, \
! { 1255, {"proacl"}, 1034, -1, -1, 22, 1, -1, -1, false, 'x', 'i', false, false, false, true, 0 }
DATA(insert ( 1255 proname 19 -1 NAMEDATALEN 1 0 -1 -1 f p c t f f t 0));
DATA(insert ( 1255 pronamespace 26 -1 4 2 0 -1 -1 t p i t f f t 0));
--- 295,315 ----
{ 1255, {"prorows"}, 700, -1, 4, 6, 0, -1, -1, FLOAT4PASSBYVAL, 'p', 'i', true, false, false, true, 0 }, \
{ 1255, {"provariadic"}, 26, -1, 4, 7, 0, -1, -1, true, 'p', 'i', true, false, false, true, 0 }, \
{ 1255, {"proisagg"}, 16, -1, 1, 8, 0, -1, -1, true, 'p', 'c', true, false, false, true, 0 }, \
! { 1255, {"proiswfunc"}, 16, -1, 1, 9, 0, -1, -1, true, 'p', 'c', true, false, false, true, 0 }, \
! { 1255, {"prosecdef"}, 16, -1, 1, 10, 0, -1, -1, true, 'p', 'c', true, false, false, true, 0 }, \
! { 1255, {"proisstrict"}, 16, -1, 1, 11, 0, -1, -1, true, 'p', 'c', true, false, false, true, 0 }, \
! { 1255, {"proretset"}, 16, -1, 1, 12, 0, -1, -1, true, 'p', 'c', true, false, false, true, 0 }, \
! { 1255, {"provolatile"}, 18, -1, 1, 13, 0, -1, -1, true, 'p', 'c', true, false, false, true, 0 }, \
! { 1255, {"pronargs"}, 21, -1, 2, 14, 0, -1, -1, true, 'p', 's', true, false, false, true, 0 }, \
! { 1255, {"prorettype"}, 26, -1, 4, 15, 0, -1, -1, true, 'p', 'i', true, false, false, true, 0 }, \
! { 1255, {"proargtypes"}, 30, -1, -1, 16, 1, -1, -1, false, 'p', 'i', true, false, false, true, 0 }, \
! { 1255, {"proallargtypes"}, 1028, -1, -1, 17, 1, -1, -1, false, 'x', 'i', false, false, false, true, 0 }, \
! { 1255, {"proargmodes"}, 1002, -1, -1, 18, 1, -1, -1, false, 'x', 'i', false, false, false, true, 0 }, \
! { 1255, {"proargnames"}, 1009, -1, -1, 19, 1, -1, -1, false, 'x', 'i', false, false, false, true, 0 }, \
! { 1255, {"prosrc"}, 25, -1, -1, 20, 0, -1, -1, false, 'x', 'i', false, false, false, true, 0 }, \
! { 1255, {"probin"}, 17, -1, -1, 21, 0, -1, -1, false, 'x', 'i', false, false, false, true, 0 }, \
! { 1255, {"proconfig"}, 1009, -1, -1, 22, 1, -1, -1, false, 'x', 'i', false, false, false, true, 0 }, \
! { 1255, {"proacl"}, 1034, -1, -1, 23, 1, -1, -1, false, 'x', 'i', false, false, false, true, 0 }
DATA(insert ( 1255 proname 19 -1 NAMEDATALEN 1 0 -1 -1 f p c t f f t 0));
DATA(insert ( 1255 pronamespace 26 -1 4 2 0 -1 -1 t p i t f f t 0));
***************
*** 318,337 **** DATA(insert ( 1255 procost 700 -1 4 5 0 -1 -1 FLOAT4PASSBYVAL p i t f f t
DATA(insert ( 1255 prorows 700 -1 4 6 0 -1 -1 FLOAT4PASSBYVAL p i t f f t 0));
DATA(insert ( 1255 provariadic 26 -1 4 7 0 -1 -1 t p i t f f t 0));
DATA(insert ( 1255 proisagg 16 -1 1 8 0 -1 -1 t p c t f f t 0));
! DATA(insert ( 1255 prosecdef 16 -1 1 9 0 -1 -1 t p c t f f t 0));
! DATA(insert ( 1255 proisstrict 16 -1 1 10 0 -1 -1 t p c t f f t 0));
! DATA(insert ( 1255 proretset 16 -1 1 11 0 -1 -1 t p c t f f t 0));
! DATA(insert ( 1255 provolatile 18 -1 1 12 0 -1 -1 t p c t f f t 0));
! DATA(insert ( 1255 pronargs 21 -1 2 13 0 -1 -1 t p s t f f t 0));
! DATA(insert ( 1255 prorettype 26 -1 4 14 0 -1 -1 t p i t f f t 0));
! DATA(insert ( 1255 proargtypes 30 -1 -1 15 1 -1 -1 f p i t f f t 0));
! DATA(insert ( 1255 proallargtypes 1028 -1 -1 16 1 -1 -1 f x i f f f t 0));
! DATA(insert ( 1255 proargmodes 1002 -1 -1 17 1 -1 -1 f x i f f f t 0));
! DATA(insert ( 1255 proargnames 1009 -1 -1 18 1 -1 -1 f x i f f f t 0));
! DATA(insert ( 1255 prosrc 25 -1 -1 19 0 -1 -1 f x i f f f t 0));
! DATA(insert ( 1255 probin 17 -1 -1 20 0 -1 -1 f x i f f f t 0));
! DATA(insert ( 1255 proconfig 1009 -1 -1 21 1 -1 -1 f x i f f f t 0));
! DATA(insert ( 1255 proacl 1034 -1 -1 22 1 -1 -1 f x i f f f t 0));
DATA(insert ( 1255 ctid 27 0 6 -1 0 -1 -1 f p s t f f t 0));
DATA(insert ( 1255 oid 26 0 4 -2 0 -1 -1 t p i t f f t 0));
DATA(insert ( 1255 xmin 28 0 4 -3 0 -1 -1 t p i t f f t 0));
--- 319,339 ----
DATA(insert ( 1255 prorows 700 -1 4 6 0 -1 -1 FLOAT4PASSBYVAL p i t f f t 0));
DATA(insert ( 1255 provariadic 26 -1 4 7 0 -1 -1 t p i t f f t 0));
DATA(insert ( 1255 proisagg 16 -1 1 8 0 -1 -1 t p c t f f t 0));
! DATA(insert ( 1255 proiswfunc 16 -1 1 9 0 -1 -1 t p c t f f t 0));
! DATA(insert ( 1255 prosecdef 16 -1 1 10 0 -1 -1 t p c t f f t 0));
! DATA(insert ( 1255 proisstrict 16 -1 1 11 0 -1 -1 t p c t f f t 0));
! DATA(insert ( 1255 proretset 16 -1 1 12 0 -1 -1 t p c t f f t 0));
! DATA(insert ( 1255 provolatile 18 -1 1 13 0 -1 -1 t p c t f f t 0));
! DATA(insert ( 1255 pronargs 21 -1 2 14 0 -1 -1 t p s t f f t 0));
! DATA(insert ( 1255 prorettype 26 -1 4 15 0 -1 -1 t p i t f f t 0));
! DATA(insert ( 1255 proargtypes 30 -1 -1 16 1 -1 -1 f p i t f f t 0));
! DATA(insert ( 1255 proallargtypes 1028 -1 -1 17 1 -1 -1 f x i f f f t 0));
! DATA(insert ( 1255 proargmodes 1002 -1 -1 18 1 -1 -1 f x i f f f t 0));
! DATA(insert ( 1255 proargnames 1009 -1 -1 19 1 -1 -1 f x i f f f t 0));
! DATA(insert ( 1255 prosrc 25 -1 -1 20 0 -1 -1 f x i f f f t 0));
! DATA(insert ( 1255 probin 17 -1 -1 21 0 -1 -1 f x i f f f t 0));
! DATA(insert ( 1255 proconfig 1009 -1 -1 22 1 -1 -1 f x i f f f t 0));
! DATA(insert ( 1255 proacl 1034 -1 -1 23 1 -1 -1 f x i f f f t 0));
DATA(insert ( 1255 ctid 27 0 6 -1 0 -1 -1 f p s t f f t 0));
DATA(insert ( 1255 oid 26 0 4 -2 0 -1 -1 t p i t f f t 0));
DATA(insert ( 1255 xmin 28 0 4 -3 0 -1 -1 t p i t f f t 0));
*** a/src/include/catalog/pg_class.h
--- b/src/include/catalog/pg_class.h
***************
*** 125,131 **** DATA(insert OID = 1247 ( pg_type PGNSP 71 PGUID 0 1247 0 0 0 0 0 f f r 28 0 t
DESCR("");
DATA(insert OID = 1249 ( pg_attribute PGNSP 75 PGUID 0 1249 0 0 0 0 0 f f r 17 0 f f f f f 3 _null_ _null_ ));
DESCR("");
! DATA(insert OID = 1255 ( pg_proc PGNSP 81 PGUID 0 1255 0 0 0 0 0 f f r 22 0 t f f f f 3 _null_ _null_ ));
DESCR("");
DATA(insert OID = 1259 ( pg_class PGNSP 83 PGUID 0 1259 0 0 0 0 0 f f r 24 0 t f f f f 3 _null_ _null_ ));
DESCR("");
--- 125,131 ----
DESCR("");
DATA(insert OID = 1249 ( pg_attribute PGNSP 75 PGUID 0 1249 0 0 0 0 0 f f r 17 0 f f f f f 3 _null_ _null_ ));
DESCR("");
! DATA(insert OID = 1255 ( pg_proc PGNSP 81 PGUID 0 1255 0 0 0 0 0 f f r 23 0 t f f f f 3 _null_ _null_ ));
DESCR("");
DATA(insert OID = 1259 ( pg_class PGNSP 83 PGUID 0 1259 0 0 0 0 0 f f r 24 0 t f f f f 3 _null_ _null_ ));
DESCR("");