diff options
Diffstat (limited to 'src/backend/nodes/nodeFuncs.c')
| -rw-r--r-- | src/backend/nodes/nodeFuncs.c | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/src/backend/nodes/nodeFuncs.c b/src/backend/nodes/nodeFuncs.c index 51459c4a43f..6f9e0536694 100644 --- a/src/backend/nodes/nodeFuncs.c +++ b/src/backend/nodes/nodeFuncs.c @@ -17,6 +17,7 @@ #include "catalog/pg_collation.h" #include "catalog/pg_type.h" #include "miscadmin.h" +#include "nodes/makefuncs.h" #include "nodes/nodeFuncs.h" #include "nodes/relation.h" #include "utils/builtins.h" @@ -548,6 +549,30 @@ exprIsLengthCoercion(const Node *expr, int32 *coercedTypmod) } /* + * relabel_to_typmod + * Add a RelabelType node that changes just the typmod of the expression. + * + * This is primarily intended to be used during planning. Therefore, it + * strips any existing RelabelType nodes to maintain the planner's invariant + * that there are not adjacent RelabelTypes, and it uses COERCE_DONTCARE + * which would typically be inappropriate earlier. + */ +Node * +relabel_to_typmod(Node *expr, int32 typmod) +{ + Oid type = exprType(expr); + Oid coll = exprCollation(expr); + + /* Strip any existing RelabelType node(s) */ + while (expr && IsA(expr, RelabelType)) + expr = (Node *) ((RelabelType *) expr)->arg; + + /* Apply new typmod, preserving the previous exposed type and collation */ + return (Node *) makeRelabelType((Expr *) expr, type, typmod, coll, + COERCE_DONTCARE); +} + +/* * expression_returns_set * Test whether an expression returns a set result. * @@ -2694,7 +2719,9 @@ query_or_expression_tree_mutator(Node *node, * that could appear under it, but not other statement types. */ bool - raw_expression_tree_walker(Node *node, bool (*walker) (), void *context) +raw_expression_tree_walker(Node *node, + bool (*walker) (), + void *context) { ListCell *temp; |