Re: 8.4beta[12] set returning function fails -- was O.K. with 8.3 - Mailing list pgsql-hackers

Hitoshi Harada <umi.tanuki@gmail.com> writes:
> 2009/6/11 J. Greg Davidson <jgd@well.com>:
>> -- BREAKS IN PG 8.4 beta1 & beta2, vis:
>> -- � � �ERROR: �0A000: set-valued function called in context that cannot accept a set

> I am not completely sure but rsi->expectedDesc check seems not needed
> as before. All regression tests passed.

Actually that check was protecting some code in execQual.c that would
fall over if the function tried to return a tuplestore.  But it turned
out to be pretty simple to fix, so I did so.
        regards, tom lane

Index: src/backend/executor/execQual.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/executor/execQual.c,v
retrieving revision 1.249
diff -c -r1.249 execQual.c
*** src/backend/executor/execQual.c    11 Jun 2009 14:48:57 -0000    1.249
--- src/backend/executor/execQual.c    11 Jun 2009 17:14:41 -0000
***************
*** 1089,1097 ****             fcache->funcResultDesc = tupdesc;             fcache->funcReturnsTuple = false;
}        else         {
 
!             /* Else, we will complain if function wants materialize mode */             fcache->funcResultDesc =
NULL;        } 
 
--- 1089,1103 ----             fcache->funcResultDesc = tupdesc;             fcache->funcReturnsTuple = false;
}
+         else if (functypclass == TYPEFUNC_RECORD)
+         {
+             /* This will work if function doesn't need an expectedDesc */
+             fcache->funcResultDesc = NULL;
+             fcache->funcReturnsTuple = true;
+         }         else         {
!             /* Else, we will fail if function needs an expectedDesc */             fcache->funcResultDesc = NULL;
   } 
 
***************
*** 1252,1269 ****     if (fcache->funcResultSlot == NULL)     {         /* Create a slot so we can read data out of
thetuplestore */         MemoryContext oldcontext; 
 
!         /* We must have been able to determine the result rowtype */
!         if (fcache->funcResultDesc == NULL)             ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),                     errmsg("function returning setof record called in "
                    "context that cannot accept type record"))); 
 
!         oldcontext = MemoryContextSwitchTo(fcache->func.fn_mcxt);
!         fcache->funcResultSlot =
!             MakeSingleTupleTableSlot(fcache->funcResultDesc);         MemoryContextSwitchTo(oldcontext);     } 
--- 1258,1289 ----     if (fcache->funcResultSlot == NULL)     {         /* Create a slot so we can read data out of
thetuplestore */
 
+         TupleDesc    slotDesc;         MemoryContext oldcontext; 
!         oldcontext = MemoryContextSwitchTo(fcache->func.fn_mcxt);
! 
!         /*
!          * If we were not able to determine the result rowtype from context,
!          * and the function didn't return a tupdesc, we have to fail.
!          */
!         if (fcache->funcResultDesc)
!             slotDesc = fcache->funcResultDesc;
!         else if (resultDesc)
!         {
!             /* don't assume resultDesc is long-lived */
!             slotDesc = CreateTupleDescCopy(resultDesc);
!         }
!         else
!         {             ereport(ERROR,                     (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("function returning setof record called in "                             "context that cannot accept type
record")));
+             slotDesc = NULL;    /* keep compiler quiet */
+         } 
!         fcache->funcResultSlot = MakeSingleTupleTableSlot(slotDesc);         MemoryContextSwitchTo(oldcontext);     }

Index: src/backend/executor/functions.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/executor/functions.c,v
retrieving revision 1.134
diff -c -r1.134 functions.c
*** src/backend/executor/functions.c    11 Jun 2009 14:48:57 -0000    1.134
--- src/backend/executor/functions.c    11 Jun 2009 17:14:41 -0000
***************
*** 634,644 ****          * For simplicity, we require callers to support both set eval modes.          * There are
caseswhere we must use one or must use the other, and          * it's not really worthwhile to postpone the check till
weknow.          */         if (!rsi || !IsA(rsi, ReturnSetInfo) ||             (rsi->allowedModes & SFRM_ValuePerCall)
==0 ||
 
!             (rsi->allowedModes & SFRM_Materialize) == 0 ||
!             rsi->expectedDesc == NULL)             ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),                     errmsg("set-valued function called in context that cannot
accepta set")));
 
--- 634,644 ----          * For simplicity, we require callers to support both set eval modes.          * There are
caseswhere we must use one or must use the other, and          * it's not really worthwhile to postpone the check till
weknow.
 
+          * But note we do not require caller to provide an expectedDesc.          */         if (!rsi || !IsA(rsi,
ReturnSetInfo)||             (rsi->allowedModes & SFRM_ValuePerCall) == 0 ||
 
!             (rsi->allowedModes & SFRM_Materialize) == 0)             ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),                     errmsg("set-valued function called in context that cannot
accepta set")));
 
Index: src/test/regress/expected/rangefuncs.out
===================================================================
RCS file: /cvsroot/pgsql/src/test/regress/expected/rangefuncs.out,v
retrieving revision 1.21
diff -c -r1.21 rangefuncs.out
*** src/test/regress/expected/rangefuncs.out    30 Mar 2009 04:08:43 -0000    1.21
--- src/test/regress/expected/rangefuncs.out    11 Jun 2009 17:14:42 -0000
***************
*** 763,765 ****
--- 763,832 ---- (1 row)  drop function foo1(n integer);
+ -- test use of SQL functions returning record
+ -- this is supported in some cases where the query doesn't specify
+ -- the actual record type ...
+ create function array_to_set(anyarray) returns setof record as $$
+   select i AS "index", $1[i] AS "value" from generate_subscripts($1, 1) i
+ $$ language sql strict immutable;
+ select array_to_set(array['one', 'two']);
+  array_to_set 
+ --------------
+  (1,one)
+  (2,two)
+ (2 rows)
+ 
+ select * from array_to_set(array['one', 'two']) as t(f1 int,f2 text);
+  f1 | f2  
+ ----+-----
+   1 | one
+   2 | two
+ (2 rows)
+ 
+ select * from array_to_set(array['one', 'two']); -- fail
+ ERROR:  a column definition list is required for functions returning "record"
+ LINE 1: select * from array_to_set(array['one', 'two']);
+                       ^
+ create temp table foo(f1 int8, f2 int8);
+ create function testfoo() returns record as $$
+   insert into foo values (1,2) returning *;
+ $$ language sql;
+ select testfoo();
+  testfoo 
+ ---------
+  (1,2)
+ (1 row)
+ 
+ select * from testfoo() as t(f1 int8,f2 int8);
+  f1 | f2 
+ ----+----
+   1 |  2
+ (1 row)
+ 
+ select * from testfoo(); -- fail
+ ERROR:  a column definition list is required for functions returning "record"
+ LINE 1: select * from testfoo();
+                       ^
+ drop function testfoo();
+ create function testfoo() returns setof record as $$
+   insert into foo values (1,2), (3,4) returning *;
+ $$ language sql;
+ select testfoo();
+  testfoo 
+ ---------
+  (1,2)
+  (3,4)
+ (2 rows)
+ 
+ select * from testfoo() as t(f1 int8,f2 int8);
+  f1 | f2 
+ ----+----
+   1 |  2
+   3 |  4
+ (2 rows)
+ 
+ select * from testfoo(); -- fail
+ ERROR:  a column definition list is required for functions returning "record"
+ LINE 1: select * from testfoo();
+                       ^
+ drop function testfoo();
Index: src/test/regress/sql/rangefuncs.sql
===================================================================
RCS file: /cvsroot/pgsql/src/test/regress/sql/rangefuncs.sql,v
retrieving revision 1.10
diff -c -r1.10 rangefuncs.sql
*** src/test/regress/sql/rangefuncs.sql    30 Mar 2009 04:08:43 -0000    1.10
--- src/test/regress/sql/rangefuncs.sql    11 Jun 2009 17:14:42 -0000
***************
*** 351,353 ****
--- 351,387 ---- select t.a, t, t.a from foo1(10000) t limit 1;  drop function foo1(n integer);
+ 
+ -- test use of SQL functions returning record
+ -- this is supported in some cases where the query doesn't specify
+ -- the actual record type ...
+ 
+ create function array_to_set(anyarray) returns setof record as $$
+   select i AS "index", $1[i] AS "value" from generate_subscripts($1, 1) i
+ $$ language sql strict immutable;
+ 
+ select array_to_set(array['one', 'two']);
+ select * from array_to_set(array['one', 'two']) as t(f1 int,f2 text);
+ select * from array_to_set(array['one', 'two']); -- fail
+ 
+ create temp table foo(f1 int8, f2 int8);
+ 
+ create function testfoo() returns record as $$
+   insert into foo values (1,2) returning *;
+ $$ language sql;
+ 
+ select testfoo();
+ select * from testfoo() as t(f1 int8,f2 int8);
+ select * from testfoo(); -- fail
+ 
+ drop function testfoo();
+ 
+ create function testfoo() returns setof record as $$
+   insert into foo values (1,2), (3,4) returning *;
+ $$ language sql;
+ 
+ select testfoo();
+ select * from testfoo() as t(f1 int8,f2 int8);
+ select * from testfoo(); -- fail
+ 
+ drop function testfoo();