index 4838ef18e6bab2a25345d97b8ba22409f31ba1c0..b3789d8efcfafeea815b8bfd29cf519e92adc4fb 100644 (file)
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/executor/execScan.c,v 1.39 2007年01月05日 22:19:27 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/executor/execScan.c,v 1.40 2007年01月24日 01:25:47 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -215,8 +215,18 @@ tlist_matches_tupdesc(PlanState *ps, List *tlist, Index varno, TupleDesc tupdesc
return false; /* out of order */
if (att_tup->attisdropped)
return false; /* table contains dropped columns */
+ /*
+ * Note: usually the Var's type should match the tupdesc exactly,
+ * but in situations involving unions of columns that have different
+ * typmods, the Var may have come from above the union and hence have
+ * typmod -1. This is a legitimate situation since the Var still
+ * describes the column, just not as exactly as the tupdesc does.
+ * We could change the planner to prevent it, but it'd then insert
+ * projection steps just to convert from specific typmod to typmod -1,
+ * which is pretty silly.
+ */
Assert(var->vartype == att_tup->atttypid);
- Assert(var->vartypmod == att_tup->atttypmod);
+ Assert(var->vartypmod == att_tup->atttypmod || var->vartypmod == -1);
tlist_item = lnext(tlist_item);
}