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, 14 insertions, 23 deletions

diff --git a/src/backend/rewrite/rewriteHandler.c b/src/backend/rewrite/rewriteHandler.c
index 95fc726227f..0b2d839eb3f 100644
--- a/src/backend/rewrite/rewriteHandler.c
+++ b/src/backend/rewrite/rewriteHandler.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteHandler.c,v 1.109 2002/09/11 14:48:54 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteHandler.c,v 1.110 2002/09/18 21:35:22 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -25,7 +25,6 @@
 #include "parser/parse_coerce.h"
 #include "parser/parse_expr.h"
 #include "parser/parse_oper.h"
-#include "parser/parse_target.h"
 #include "parser/parse_type.h"
 #include "parser/parsetree.h"
 #include "rewrite/rewriteHandler.h"
@@ -474,29 +473,21 @@ build_column_default(Relation rel, int attrno)
 	 */
 	exprtype = exprType(expr);
 
-	if (exprtype != atttype)
-	{
-		expr = CoerceTargetExpr(NULL, expr, exprtype,
-								atttype, atttypmod, false);
-
-		/*
-		 * This really shouldn't fail; should have checked the default's
-		 * type when it was created ...
-		 */
-		if (expr == NULL)
-			elog(ERROR, "Column \"%s\" is of type %s"
-				 " but default expression is of type %s"
-				 "\n\tYou will need to rewrite or cast the expression",
-				 NameStr(att_tup->attname),
-				 format_type_be(atttype),
-				 format_type_be(exprtype));
-	}
-
+	expr = coerce_to_target_type(expr, exprtype,
+								 atttype, atttypmod,
+								 COERCION_ASSIGNMENT,
+								 COERCE_IMPLICIT_CAST);
 	/*
-	 * If the column is a fixed-length type, it may need a length coercion
-	 * as well as a type coercion.
+	 * This really shouldn't fail; should have checked the default's
+	 * type when it was created ...
 	 */
-	expr = coerce_type_typmod(NULL, expr, atttype, atttypmod);
+	if (expr == NULL)
+		elog(ERROR, "Column \"%s\" is of type %s"
+			 " but default expression is of type %s"
+			 "\n\tYou will need to rewrite or cast the expression",
+			 NameStr(att_tup->attname),
+			 format_type_be(atttype),
+			 format_type_be(exprtype));
 
 	return expr;
 }