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, 68 insertions, 1 deletions

diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index 5d53eca999f..f8643388970 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/arrayfuncs.c,v 1.80 2002/09/04 20:31:27 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/arrayfuncs.c,v 1.81 2002/09/18 21:35:22 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -19,6 +19,7 @@
 #include "access/tupmacs.h"
 #include "catalog/catalog.h"
 #include "catalog/pg_type.h"
+#include "parser/parse_coerce.h"
 #include "utils/array.h"
 #include "utils/memutils.h"
 #include "utils/syscache.h"
@@ -755,6 +756,72 @@ array_out(PG_FUNCTION_ARGS)
 	PG_RETURN_CSTRING(retval);
 }
 
+/*-------------------------------------------------------------------------
+ * array_length_coerce :
+ *		  Apply the element type's length-coercion routine to each element
+ *		  of the given array.
+ *-------------------------------------------------------------------------
+ */
+Datum
+array_length_coerce(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int32		len = PG_GETARG_INT32(1);
+	bool		isExplicit = PG_GETARG_BOOL(2);
+	FmgrInfo   *fmgr_info = fcinfo->flinfo;
+	FmgrInfo   *element_finfo;
+	FunctionCallInfoData locfcinfo;
+
+	/* If no typmod is provided, shortcircuit the whole thing */
+	if (len < 0)
+		PG_RETURN_ARRAYTYPE_P(v);
+
+	/*
+	 * We arrange to look up the element type's coercion function only
+	 * once per series of calls.
+	 */
+	if (fmgr_info->fn_extra == NULL)
+	{
+		Oid			funcId;
+		int			nargs;
+
+		fmgr_info->fn_extra = MemoryContextAlloc(fmgr_info->fn_mcxt,
+												 sizeof(FmgrInfo));
+		element_finfo = (FmgrInfo *) fmgr_info->fn_extra;
+
+		funcId = find_typmod_coercion_function(ARR_ELEMTYPE(v), &nargs);
+
+		if (OidIsValid(funcId))
+			fmgr_info_cxt(funcId, element_finfo, fmgr_info->fn_mcxt);
+		else
+			element_finfo->fn_oid = InvalidOid;
+	}
+	else
+		element_finfo = (FmgrInfo *) fmgr_info->fn_extra;
+
+	/*
+	 * If we didn't find a coercion function, return the array unmodified
+	 * (this should not happen in the normal course of things, but might
+	 * happen if this function is called manually).
+	 */
+	if (element_finfo->fn_oid == InvalidOid)
+		PG_RETURN_ARRAYTYPE_P(v);
+
+	/*
+	 * Use array_map to apply the function to each array element.
+	 *
+	 * Note: we pass isExplicit whether or not the function wants it ...
+	 */
+	MemSet(&locfcinfo, 0, sizeof(locfcinfo));
+	locfcinfo.flinfo = element_finfo;
+	locfcinfo.nargs = 3;
+	locfcinfo.arg[0] = PointerGetDatum(v);
+	locfcinfo.arg[1] = Int32GetDatum(len);
+	locfcinfo.arg[2] = BoolGetDatum(isExplicit);
+
+	return array_map(&locfcinfo, ARR_ELEMTYPE(v), ARR_ELEMTYPE(v));
+}
+
 /*-----------------------------------------------------------------------------
  * array_dims :
  *		  returns the dimensions of the array pointed to by "v", as a "text"