Extend pg_cast castimplicit column to a three-way value; this allows us

to be flexible about assignment casts without introducing ambiguity in
operator/function resolution.  Introduce a well-defined promotion hierarchy
for numeric datatypes (int2->int4->int8->numeric->float4->float8).
Change make_const to initially label numeric literals as int4, int8, or
numeric (never float8 anymore).
Explicitly mark Func and RelabelType nodes to indicate whether they came
from a function call, explicit cast, or implicit cast; use this to do
reverse-listing more accurately and without so many heuristics.
Explicit casts to char, varchar, bit, varbit will truncate or pad without
raising an error (the pre-7.2 behavior), while assigning to a column without
any explicit cast will still raise an error for wrong-length data like 7.3.
This more nearly follows the SQL spec than 7.2 behavior (we should be
reporting a 'completion condition' in the explicit-cast cases, but we have
no mechanism for that, so just do silent truncation).
Fix some problems with enforcement of typmod for array elements;
it didn't work at all in 'UPDATE ... SET array[n] = foo', for example.
Provide a generalized array_length_coerce() function to replace the
specialized per-array-type functions that used to be needed (and were
missing for NUMERIC as well as all the datetime types).
Add missing conversions int8<->float4, text<->numeric, oid<->int8.
initdb forced.

1 files changed, 11 insertions, 7 deletions

diff --git a/src/backend/parser/parse_clause.c b/src/backend/parser/parse_clause.c
index a46ff5e2fcd..245c0ba422b 100644
--- a/src/backend/parser/parse_clause.c
+++ b/src/backend/parser/parse_clause.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_clause.c,v 1.97 2002/09/04 20:31:23 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_clause.c,v 1.98 2002/09/18 21:35:22 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -872,20 +872,24 @@ buildMergedJoinVar(JoinType jointype, Var *l_colvar, Var *r_colvar)
 	 * typmod is not same as input.
 	 */
 	if (l_colvar->vartype != outcoltype)
-		l_node = coerce_type(NULL, (Node *) l_colvar, l_colvar->vartype,
-							 outcoltype, outcoltypmod, false);
+		l_node = coerce_type((Node *) l_colvar, l_colvar->vartype,
+							 outcoltype,
+							 COERCION_IMPLICIT, COERCE_IMPLICIT_CAST);
 	else if (l_colvar->vartypmod != outcoltypmod)
 		l_node = (Node *) makeRelabelType((Node *) l_colvar,
-										  outcoltype, outcoltypmod);
+										  outcoltype, outcoltypmod,
+										  COERCE_IMPLICIT_CAST);
 	else
 		l_node = (Node *) l_colvar;
 
 	if (r_colvar->vartype != outcoltype)
-		r_node = coerce_type(NULL, (Node *) r_colvar, r_colvar->vartype,
-							 outcoltype, outcoltypmod, false);
+		r_node = coerce_type((Node *) r_colvar, r_colvar->vartype,
+							 outcoltype,
+							 COERCION_IMPLICIT, COERCE_IMPLICIT_CAST);
 	else if (r_colvar->vartypmod != outcoltypmod)
 		r_node = (Node *) makeRelabelType((Node *) r_colvar,
-										  outcoltype, outcoltypmod);
+										  outcoltype, outcoltypmod,
+										  COERCE_IMPLICIT_CAST);
 	else
 		r_node = (Node *) r_colvar;