Get rid of ParseState.p_value_substitute; use a columnref hook instead.

I noticed that p_value_substitute, which is a single-purpose kluge I added
in 2002 (commit b0422b215), could be replaced by having domainAddConstraint
install a parser hook that looks for the name "value".  The parser hook
code only dates back to 2009, so it's not surprising that we had to kluge
this in 2002, but we can do it more cleanly now.

1 files changed, 0 insertions, 21 deletions

diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c
index 38c2535b65f..f62e45f8ac8 100644
--- a/src/backend/parser/parse_expr.c
+++ b/src/backend/parser/parse_expr.c
@@ -577,27 +577,6 @@ transformColumnRef(ParseState *pstate, ColumnRef *cref)
 					/*
 					 * Not known as a column of any range-table entry.
 					 *
-					 * Consider the possibility that it's VALUE in a domain
-					 * check expression.  (We handle VALUE as a name, not a
-					 * keyword, to avoid breaking a lot of applications that
-					 * have used VALUE as a column name in the past.)
-					 */
-					if (pstate->p_value_substitute != NULL &&
-						strcmp(colname, "value") == 0)
-					{
-						node = (Node *) copyObject(pstate->p_value_substitute);
-
-						/*
-						 * Try to propagate location knowledge.  This should
-						 * be extended if p_value_substitute can ever take on
-						 * other node types.
-						 */
-						if (IsA(node, CoerceToDomainValue))
-							((CoerceToDomainValue *) node)->location = cref->location;
-						break;
-					}
-
-					/*
 					 * Try to find the name as a relation.  Note that only
 					 * relations already entered into the rangetable will be
 					 * recognized.