diff options
Diffstat (limited to 'src/backend/optimizer')
| -rw-r--r-- | src/backend/optimizer/util/clauses.c | 45 |
1 files changed, 44 insertions, 1 deletions
diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c index 664a0dfaaa5..4bb84f15214 100644 --- a/src/backend/optimizer/util/clauses.c +++ b/src/backend/optimizer/util/clauses.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/optimizer/util/clauses.c,v 1.59 2000/02/15 03:37:36 thomas Exp $ + * $Header: /cvsroot/pgsql/src/backend/optimizer/util/clauses.c,v 1.60 2000/02/20 21:32:06 tgl Exp $ * * HISTORY * AUTHOR DATE MAJOR EVENT @@ -1150,6 +1150,37 @@ eval_const_expressions_mutator (Node *node, void *context) newexpr->args = args; return (Node *) newexpr; } + if (IsA(node, RelabelType)) + { + /* + * If we can simplify the input to a constant, then we don't need + * the RelabelType node anymore: just change the type field of + * the Const node. Otherwise keep the RelabelType node. + * + * XXX if relabel has a nondefault resulttypmod, do we need to + * keep it to show that? At present I don't think so. + */ + RelabelType *relabel = (RelabelType *) node; + Node *arg; + + arg = eval_const_expressions_mutator(relabel->arg, context); + if (arg && IsA(arg, Const)) + { + Const *con = (Const *) arg; + + con->consttype = relabel->resulttype; + return (Node *) con; + } + else + { + RelabelType *newrelabel = makeNode(RelabelType); + + newrelabel->arg = arg; + newrelabel->resulttype = relabel->resulttype; + newrelabel->resulttypmod = relabel->resulttypmod; + return (Node *) newrelabel; + } + } if (IsA(node, CaseExpr)) { /* @@ -1392,6 +1423,8 @@ expression_tree_walker(Node *node, bool (*walker) (), void *context) return true; } break; + case T_RelabelType: + return walker(((RelabelType *) node)->arg, context); case T_CaseExpr: { CaseExpr *caseexpr = (CaseExpr *) node; @@ -1603,6 +1636,16 @@ expression_tree_mutator(Node *node, Node * (*mutator) (), void *context) return (Node *) newnode; } break; + case T_RelabelType: + { + RelabelType *relabel = (RelabelType *) node; + RelabelType *newnode; + + FLATCOPY(newnode, relabel, RelabelType); + MUTATE(newnode->arg, relabel->arg, Node *); + return (Node *) newnode; + } + break; case T_CaseExpr: { CaseExpr *caseexpr = (CaseExpr *) node; |