From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Thu, 26 Aug 2010 18:55:12 +0000 (+0000)
Subject: Fix ExecMakeTableFunctionResult to verify that all rows returned by a SRF
X-Git-Tag: REL8_1_22~16
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c2c90a543082f1c3d3ae739ef7eabed8abfac6cd;p=thirdparty%2Fpostgresql.git

Fix ExecMakeTableFunctionResult to verify that all rows returned by a SRF
returning "record" actually do have the same rowtype.  This is needed because
the parser can't realistically enforce that they will all have the same typmod,
as seen in a recent example from David Wheeler.

Back-patch to 8.0, which is as far back as we have the notion of RECORD
subtypes being distinguished by typmod.  Wheeler's example depends on
8.4-and-up features, but I suspect there may be ways to provoke similar
failures before 8.4.
---

diff --git a/src/backend/executor/execQual.c b/src/backend/executor/execQual.c
index 57536cd0938..9ccd89f1cc6 100644
--- a/src/backend/executor/execQual.c
+++ b/src/backend/executor/execQual.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/executor/execQual.c,v 1.183.2.7 2009/12/29 17:41:35 heikki Exp $
+ *	  $PostgreSQL: pgsql/src/backend/executor/execQual.c,v 1.183.2.8 2010/08/26 18:55:12 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1509,6 +1509,16 @@ ExecMakeTableFunctionResult(ExprState *funcexpr,
 
 				td = DatumGetHeapTupleHeader(result);
 
+				/*
+				 * Verify all returned rows have same subtype; necessary in
+				 * case the type is RECORD.
+				 */
+				if (HeapTupleHeaderGetTypeId(td) != tupdesc->tdtypeid ||
+					HeapTupleHeaderGetTypMod(td) != tupdesc->tdtypmod)
+					ereport(ERROR,
+							(errcode(ERRCODE_DATATYPE_MISMATCH),
+							 errmsg("rows returned by function are not all of the same row type")));
+
 				/*
 				 * tuplestore_puttuple needs a HeapTuple not a bare
 				 * HeapTupleHeader, but it doesn't need all the fields.