diff options
| -rw-r--r-- | src/backend/optimizer/plan/setrefs.c | 32 |
1 files changed, 24 insertions, 8 deletions
diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c index 96692544634..3f3a7199417 100644 --- a/src/backend/optimizer/plan/setrefs.c +++ b/src/backend/optimizer/plan/setrefs.c @@ -9,7 +9,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/plan/setrefs.c,v 1.124 2006/08/12 02:52:05 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/plan/setrefs.c,v 1.125 2006/08/28 14:32:41 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -448,16 +448,32 @@ trivial_subqueryscan(SubqueryScan *plan) { TargetEntry *ptle = (TargetEntry *) lfirst(lp); TargetEntry *ctle = (TargetEntry *) lfirst(lc); - Var *var = (Var *) ptle->expr; if (ptle->resjunk != ctle->resjunk) return false; /* tlist doesn't match junk status */ - if (!var || !IsA(var, Var)) - return false; /* tlist item not a Var */ - Assert(var->varno == plan->scan.scanrelid); - Assert(var->varlevelsup == 0); - if (var->varattno != attrno) - return false; /* out of order */ + + /* + * We accept either a Var referencing the corresponding element of + * the subplan tlist, or a Const equaling the subplan element. + * See generate_setop_tlist() for motivation. + */ + if (ptle->expr && IsA(ptle->expr, Var)) + { + Var *var = (Var *) ptle->expr; + + Assert(var->varno == plan->scan.scanrelid); + Assert(var->varlevelsup == 0); + if (var->varattno != attrno) + return false; /* out of order */ + } + else if (ptle->expr && IsA(ptle->expr, Const)) + { + if (!equal(ptle->expr, ctle->expr)) + return false; + } + else + return false; + attrno++; } |