Fix up the remaining places where the expression node structure would lose

available information about the typmod of an expression; namely, Const,
ArrayRef, ArrayExpr, and EXPR and ARRAY SubLinks.  In the ArrayExpr and
SubLink cases it wasn't really the data structure's fault, but exprTypmod()
being lazy.  This seems like a good idea in view of the expected increase in
typmod usage from Teodor's work to allow user-defined types to have typmods.
In particular this responds to the concerns we had about eliminating the
special-purpose hack that exprTypmod() used to have for BPCHAR Consts.
We can now tell whether or not such a Const has been cast to a specific
length, and report or display properly if so.

initdb forced due to changes in stored rules.

src/backend/nodes/copyfuncs.c

@@ -15,7 +15,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/nodes/copyfuncs.c,v 1.370 2007/03/13 00:33:40 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/nodes/copyfuncs.c,v 1.371 2007/03/17 00:11:03 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -773,6 +773,7 @@ _copyConst(Const *from)
 	Const	   *newnode = makeNode(Const);
 
 	COPY_SCALAR_FIELD(consttype);
+	COPY_SCALAR_FIELD(consttypmod);
 	COPY_SCALAR_FIELD(constlen);
 
 	if (from->constbyval || from->constisnull)
@@ -841,9 +842,9 @@ _copyArrayRef(ArrayRef *from)
 {
 	ArrayRef   *newnode = makeNode(ArrayRef);
 
-	COPY_SCALAR_FIELD(refrestype);
 	COPY_SCALAR_FIELD(refarraytype);
 	COPY_SCALAR_FIELD(refelemtype);
+	COPY_SCALAR_FIELD(reftypmod);
 	COPY_NODE_FIELD(refupperindexpr);
 	COPY_NODE_FIELD(reflowerindexpr);
 	COPY_NODE_FIELD(refexpr);

src/backend/nodes/equalfuncs.c

@@ -18,7 +18,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/nodes/equalfuncs.c,v 1.301 2007/03/13 00:33:40 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/nodes/equalfuncs.c,v 1.302 2007/03/17 00:11:03 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -139,6 +139,7 @@ static bool
 _equalConst(Const *a, Const *b)
 {
 	COMPARE_SCALAR_FIELD(consttype);
+	COMPARE_SCALAR_FIELD(consttypmod);
 	COMPARE_SCALAR_FIELD(constlen);
 	COMPARE_SCALAR_FIELD(constisnull);
 	COMPARE_SCALAR_FIELD(constbyval);
@@ -180,9 +181,9 @@ _equalAggref(Aggref *a, Aggref *b)
 static bool
 _equalArrayRef(ArrayRef *a, ArrayRef *b)
 {
-	COMPARE_SCALAR_FIELD(refrestype);
 	COMPARE_SCALAR_FIELD(refarraytype);
 	COMPARE_SCALAR_FIELD(refelemtype);
+	COMPARE_SCALAR_FIELD(reftypmod);
 	COMPARE_NODE_FIELD(refupperindexpr);
 	COMPARE_NODE_FIELD(reflowerindexpr);
 	COMPARE_NODE_FIELD(refexpr);

src/backend/nodes/makefuncs.c

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/nodes/makefuncs.c,v 1.54 2007/01/05 22:19:30 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/nodes/makefuncs.c,v 1.55 2007/03/17 00:11:03 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -140,6 +140,7 @@ flatCopyTargetEntry(TargetEntry *src_tle)
  */
 Const *
 makeConst(Oid consttype,
+		  int32 consttypmod,
 		  int constlen,
 		  Datum constvalue,
 		  bool constisnull,
@@ -148,6 +149,7 @@ makeConst(Oid consttype,
 	Const	   *cnst = makeNode(Const);
 
 	cnst->consttype = consttype;
+	cnst->consttypmod = consttypmod;
 	cnst->constlen = constlen;
 	cnst->constvalue = constvalue;
 	cnst->constisnull = constisnull;
@@ -159,6 +161,8 @@ makeConst(Oid consttype,
 /*
  * makeNullConst -
  *	  creates a Const node representing a NULL of the specified type
+ *
+ * Note: for all current uses, OK to set typmod of the Const to -1.
  */
 Const *
 makeNullConst(Oid consttype)
@@ -168,6 +172,7 @@ makeNullConst(Oid consttype)
 
 	get_typlenbyval(consttype, &typLen, &typByVal);
 	return makeConst(consttype,
+					 -1,
 					 (int) typLen,
 					 (Datum) 0,
 					 true,
@@ -182,7 +187,8 @@ Node *
 makeBoolConst(bool value, bool isnull)
 {
 	/* note that pg_type.h hardwires size of bool as 1 ... duplicate it */
-	return (Node *) makeConst(BOOLOID, 1, BoolGetDatum(value), isnull, true);
+	return (Node *) makeConst(BOOLOID, -1, 1,
+							  BoolGetDatum(value), isnull, true);
 }
 
 /*

src/backend/nodes/outfuncs.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/nodes/outfuncs.c,v 1.303 2007/03/13 00:33:40 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/nodes/outfuncs.c,v 1.304 2007/03/17 00:11:03 tgl Exp $
  *
  * NOTES
  *	  Every node type that can appear in stored rules' parsetrees *must*
@@ -685,6 +685,7 @@ _outConst(StringInfo str, Const *node)
 	WRITE_NODE_TYPE("CONST");
 
 	WRITE_OID_FIELD(consttype);
+	WRITE_INT_FIELD(consttypmod);
 	WRITE_INT_FIELD(constlen);
 	WRITE_BOOL_FIELD(constbyval);
 	WRITE_BOOL_FIELD(constisnull);
@@ -725,9 +726,9 @@ _outArrayRef(StringInfo str, ArrayRef *node)
 {
 	WRITE_NODE_TYPE("ARRAYREF");
 
-	WRITE_OID_FIELD(refrestype);
 	WRITE_OID_FIELD(refarraytype);
 	WRITE_OID_FIELD(refelemtype);
+	WRITE_INT_FIELD(reftypmod);
 	WRITE_NODE_FIELD(refupperindexpr);
 	WRITE_NODE_FIELD(reflowerindexpr);
 	WRITE_NODE_FIELD(refexpr);

src/backend/nodes/readfuncs.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/nodes/readfuncs.c,v 1.203 2007/02/20 17:32:15 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/nodes/readfuncs.c,v 1.204 2007/03/17 00:11:04 tgl Exp $
  *
  * NOTES
  *	  Path and Plan nodes do not have any readfuncs support, because we
@@ -324,6 +324,7 @@ _readConst(void)
 	READ_LOCALS(Const);
 
 	READ_OID_FIELD(consttype);
+	READ_INT_FIELD(consttypmod);
 	READ_INT_FIELD(constlen);
 	READ_BOOL_FIELD(constbyval);
 	READ_BOOL_FIELD(constisnull);
@@ -379,9 +380,9 @@ _readArrayRef(void)
 {
 	READ_LOCALS(ArrayRef);
 
-	READ_OID_FIELD(refrestype);
 	READ_OID_FIELD(refarraytype);
 	READ_OID_FIELD(refelemtype);
+	READ_INT_FIELD(reftypmod);
 	READ_NODE_FIELD(refupperindexpr);
 	READ_NODE_FIELD(reflowerindexpr);
 	READ_NODE_FIELD(refexpr);

src/backend/optimizer/path/indxpath.c

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.216 2007/01/20 20:45:39 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.217 2007/03/17 00:11:04 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -2628,7 +2628,7 @@ network_prefix_quals(Node *leftop, Oid expr_op, Oid opfamily, Datum rightop)
 
 	expr = make_opclause(opr1oid, BOOLOID, false,
 						 (Expr *) leftop,
-						 (Expr *) makeConst(datatype, -1, opr1right,
+						 (Expr *) makeConst(datatype, -1, -1, opr1right,
 											false, false));
 	result = list_make1(make_restrictinfo(expr, true, false, false, NULL));
 
@@ -2643,7 +2643,7 @@ network_prefix_quals(Node *leftop, Oid expr_op, Oid opfamily, Datum rightop)
 
 	expr = make_opclause(opr2oid, BOOLOID, false,
 						 (Expr *) leftop,
-						 (Expr *) makeConst(datatype, -1, opr2right,
+						 (Expr *) makeConst(datatype, -1, -1, opr2right,
 											false, false));
 	result = lappend(result,
 					 make_restrictinfo(expr, true, false, false, NULL));
@@ -2683,6 +2683,7 @@ string_to_const(const char *str, Oid datatype)
 {
 	Datum		conval = string_to_datum(str, datatype);
 
-	return makeConst(datatype, ((datatype == NAMEOID) ? NAMEDATALEN : -1),
+	return makeConst(datatype, -1,
+					 ((datatype == NAMEOID) ? NAMEDATALEN : -1),
 					 conval, false, false);
 }

src/backend/optimizer/plan/planagg.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/plan/planagg.c,v 1.29 2007/02/22 22:00:24 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/plan/planagg.c,v 1.30 2007/03/17 00:11:04 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -477,7 +477,7 @@ make_agg_subplan(PlannerInfo *root, MinMaxAggInfo *info)
 
 	/* set up LIMIT 1 */
 	subparse->limitOffset = NULL;
-	subparse->limitCount = (Node *) makeConst(INT8OID, sizeof(int64),
+	subparse->limitCount = (Node *) makeConst(INT8OID, -1, sizeof(int64),
 											  Int64GetDatum(1),
 											  false, false /* not by val */ );
 

src/backend/optimizer/prep/preptlist.c

@@ -16,7 +16,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/prep/preptlist.c,v 1.86 2007/02/19 07:03:30 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/prep/preptlist.c,v 1.87 2007/03/17 00:11:04 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -281,6 +281,7 @@ expand_targetlist(List *tlist, int command_type,
 					if (!att_tup->attisdropped)
 					{
 						new_expr = (Node *) makeConst(atttype,
+													  -1,
 													  att_tup->attlen,
 													  (Datum) 0,
 													  true,		/* isnull */
@@ -296,6 +297,7 @@ expand_targetlist(List *tlist, int command_type,
 					{
 						/* Insert NULL for dropped column */
 						new_expr = (Node *) makeConst(INT4OID,
+													  -1,
 													  sizeof(int32),
 													  (Datum) 0,
 													  true,		/* isnull */
@@ -315,6 +317,7 @@ expand_targetlist(List *tlist, int command_type,
 					{
 						/* Insert NULL for dropped column */
 						new_expr = (Node *) makeConst(INT4OID,
+													  -1,
 													  sizeof(int32),
 													  (Datum) 0,
 													  true,		/* isnull */

src/backend/optimizer/prep/prepunion.c

@@ -22,7 +22,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/prep/prepunion.c,v 1.139 2007/02/22 22:00:24 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/prep/prepunion.c,v 1.140 2007/03/17 00:11:04 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -545,6 +545,7 @@ generate_setop_tlist(List *colTypes, int flag,
 		/* Add a resjunk flag column */
 		/* flag value is the given constant */
 		expr = (Node *) makeConst(INT4OID,
+								  -1,
 								  sizeof(int4),
 								  Int32GetDatum(flag),
 								  false,

src/backend/optimizer/util/clauses.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.238 2007/03/13 00:33:41 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.239 2007/03/17 00:11:04 tgl Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -82,10 +82,12 @@ static List *simplify_and_arguments(List *args,
 					   eval_const_expressions_context *context,
 					   bool *haveNull, bool *forceFalse);
 static Expr *simplify_boolean_equality(List *args);
-static Expr *simplify_function(Oid funcid, Oid result_type, List *args,
+static Expr *simplify_function(Oid funcid,
+				  Oid result_type, int32 result_typmod, List *args,
 				  bool allow_inline,
 				  eval_const_expressions_context *context);
-static Expr *evaluate_function(Oid funcid, Oid result_type, List *args,
+static Expr *evaluate_function(Oid funcid,
+				  Oid result_type, int32 result_typmod, List *args,
 				  HeapTuple func_tuple,
 				  eval_const_expressions_context *context);
 static Expr *inline_function(Oid funcid, Oid result_type, List *args,
@@ -96,7 +98,7 @@ static Node *substitute_actual_parameters(Node *expr, int nargs, List *args,
 static Node *substitute_actual_parameters_mutator(Node *node,
 							  substitute_actual_parameters_context *context);
 static void sql_inline_error_callback(void *arg);
-static Expr *evaluate_expr(Expr *expr, Oid result_type);
+static Expr *evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod);
 
 
 /*****************************************************************************
@@ -934,8 +936,6 @@ contain_nonstrict_functions_walker(Node *node, void *context)
 		return true;
 	if (IsA(node, CaseExpr))
 		return true;
-	if (IsA(node, CaseWhen))
-		return true;
 	if (IsA(node, ArrayExpr))
 		return true;
 	if (IsA(node, RowExpr))
@@ -1654,6 +1654,7 @@ eval_const_expressions_mutator(Node *node,
 					else
 						pval = datumCopy(prm->value, typByVal, typLen);
 					return (Node *) makeConst(param->paramtype,
+											  param->paramtypmod,
 											  (int) typLen,
 											  pval,
 											  prm->isnull,
@@ -1682,9 +1683,13 @@ eval_const_expressions_mutator(Node *node,
 
 		/*
 		 * Code for op/func reduction is pretty bulky, so split it out as a
-		 * separate function.
+		 * separate function.  Note: exprTypmod normally returns -1 for a
+		 * FuncExpr, but not when the node is recognizably a length coercion;
+		 * we want to preserve the typmod in the eventual Const if so.
 		 */
-		simple = simplify_function(expr->funcid, expr->funcresulttype, args,
+		simple = simplify_function(expr->funcid,
+								   expr->funcresulttype, exprTypmod(node),
+								   args,
 								   true, context);
 		if (simple)				/* successfully simplified it */
 			return (Node *) simple;
@@ -1728,7 +1733,9 @@ eval_const_expressions_mutator(Node *node,
 		 * Code for op/func reduction is pretty bulky, so split it out as a
 		 * separate function.
 		 */
-		simple = simplify_function(expr->opfuncid, expr->opresulttype, args,
+		simple = simplify_function(expr->opfuncid,
+								   expr->opresulttype, -1,
+								   args,
 								   true, context);
 		if (simple)				/* successfully simplified it */
 			return (Node *) simple;
@@ -1816,8 +1823,10 @@ eval_const_expressions_mutator(Node *node,
 			 * Code for op/func reduction is pretty bulky, so split it out as
 			 * a separate function.
 			 */
-			simple = simplify_function(expr->opfuncid, expr->opresulttype,
-									   args, false, context);
+			simple = simplify_function(expr->opfuncid,
+									   expr->opresulttype, -1,
+									   args,
+									   false, context);
 			if (simple)			/* successfully simplified it */
 			{
 				/*
@@ -1961,12 +1970,7 @@ eval_const_expressions_mutator(Node *node,
 			Const	   *con = (Const *) arg;
 
 			con->consttype = relabel->resulttype;
-
-			/*
-			 * relabel's resulttypmod is discarded, which is OK for now; if
-			 * the type actually needs a runtime length coercion then there
-			 * should be a function call to do it just above this node.
-			 */
+			con->consttypmod = relabel->resulttypmod;
 			return (Node *) con;
 		}
 		else
@@ -2134,7 +2138,8 @@ eval_const_expressions_mutator(Node *node,
 
 		if (all_const)
 			return (Node *) evaluate_expr((Expr *) newarray,
-										  newarray->array_typeid);
+										  newarray->array_typeid,
+										  exprTypmod(node));
 
 		return (Node *) newarray;
 	}
@@ -2637,14 +2642,15 @@ simplify_boolean_equality(List *args)
  * (which might originally have been an operator; we don't care)
  *
  * Inputs are the function OID, actual result type OID (which is needed for
- * polymorphic functions), and the pre-simplified argument list;
+ * polymorphic functions) and typmod, and the pre-simplified argument list;
  * also the context data for eval_const_expressions.
  *
  * Returns a simplified expression if successful, or NULL if cannot
  * simplify the function call.
  */
 static Expr *
-simplify_function(Oid funcid, Oid result_type, List *args,
+simplify_function(Oid funcid, Oid result_type, int32 result_typmod,
+				  List *args,
 				  bool allow_inline,
 				  eval_const_expressions_context *context)
 {
@@ -2665,7 +2671,7 @@ simplify_function(Oid funcid, Oid result_type, List *args,
 	if (!HeapTupleIsValid(func_tuple))
 		elog(ERROR, "cache lookup failed for function %u", funcid);
 
-	newexpr = evaluate_function(funcid, result_type, args,
+	newexpr = evaluate_function(funcid, result_type, result_typmod, args,
 								func_tuple, context);
 
 	if (!newexpr && allow_inline)
@@ -2689,7 +2695,7 @@ simplify_function(Oid funcid, Oid result_type, List *args,
  * simplify the function.
  */
 static Expr *
-evaluate_function(Oid funcid, Oid result_type, List *args,
+evaluate_function(Oid funcid, Oid result_type, int32 result_typmod, List *args,
 				  HeapTuple func_tuple,
 				  eval_const_expressions_context *context)
 {
@@ -2773,7 +2779,7 @@ evaluate_function(Oid funcid, Oid result_type, List *args,
 	newexpr->funcformat = COERCE_DONTCARE;		/* doesn't matter */
 	newexpr->args = args;
 
-	return evaluate_expr((Expr *) newexpr, result_type);
+	return evaluate_expr((Expr *) newexpr, result_type, result_typmod);
 }
 
 /*
@@ -3133,7 +3139,7 @@ sql_inline_error_callback(void *arg)
  * code and ensure we get the same result as the executor would get.
  */
 static Expr *
-evaluate_expr(Expr *expr, Oid result_type)
+evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod)
 {
 	EState	   *estate;
 	ExprState  *exprstate;
@@ -3184,7 +3190,7 @@ evaluate_expr(Expr *expr, Oid result_type)
 	/*
 	 * Make the constant result node.
 	 */
-	return (Expr *) makeConst(result_type, resultTypLen,
+	return (Expr *) makeConst(result_type, result_typmod, resultTypLen,
 							  const_val, const_is_null,
 							  resultTypByVal);
 }

src/backend/optimizer/util/predtest.c

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/util/predtest.c,v 1.13 2007/01/05 22:19:33 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/util/predtest.c,v 1.14 2007/03/17 00:11:04 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -828,6 +828,7 @@ arrayconst_startup_fn(Node *clause, PredIterInfo info)
 	/* Set up a dummy Const node to hold the per-element values */
 	state->constexpr.xpr.type = T_Const;
 	state->constexpr.consttype = ARR_ELEMTYPE(arrayval);
+	state->constexpr.consttypmod = -1;
 	state->constexpr.constlen = elmlen;
 	state->constexpr.constbyval = elmbyval;
 	lsecond(state->opexpr.args) = &state->constexpr;

src/backend/parser/parse_coerce.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/parser/parse_coerce.c,v 2.150 2007/01/05 22:19:34 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/parser/parse_coerce.c,v 2.151 2007/03/17 00:11:04 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -186,6 +186,7 @@ coerce_type(ParseState *pstate, Node *node,
 		targetType = typeidType(baseTypeId);
 
 		newcon->consttype = baseTypeId;
+		newcon->consttypmod = -1;
 		newcon->constlen = typeLen(targetType);
 		newcon->constbyval = typeByVal(targetType);
 		newcon->constisnull = con->constisnull;
@@ -661,6 +662,7 @@ build_coercion_expression(Node *node, Oid funcId,
 	{
 		/* Pass target typmod as an int4 constant */
 		cons = makeConst(INT4OID,
+						 -1,
 						 sizeof(int32),
 						 Int32GetDatum(targetTypMod),
 						 false,
@@ -673,6 +675,7 @@ build_coercion_expression(Node *node, Oid funcId,
 	{
 		/* Pass it a boolean isExplicit parameter, too */
 		cons = makeConst(BOOLOID,
+						 -1,
 						 sizeof(bool),
 						 BoolGetDatum(isExplicit),
 						 false,

src/backend/parser/parse_expr.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/parser/parse_expr.c,v 1.212 2007/02/22 22:00:25 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/parser/parse_expr.c,v 1.213 2007/03/17 00:11:04 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -312,7 +312,7 @@ transformIndirection(ParseState *pstate, Node *basenode, List *indirection)
 														   result,
 														   exprType(result),
 														   InvalidOid,
-														   -1,
+														   exprTypmod(result),
 														   subscripts,
 														   NULL);
 			subscripts = NIL;
@@ -330,7 +330,7 @@ transformIndirection(ParseState *pstate, Node *basenode, List *indirection)
 												   result,
 												   exprType(result),
 												   InvalidOid,
-												   -1,
+												   exprTypmod(result),
 												   subscripts,
 												   NULL);
 
@@ -1705,7 +1705,15 @@ exprType(Node *expr)
 			type = ((Aggref *) expr)->aggtype;
 			break;
 		case T_ArrayRef:
-			type = ((ArrayRef *) expr)->refrestype;
+			{
+				ArrayRef   *arrayref = (ArrayRef *) expr;
+
+				/* slice and/or store operations yield the array type */
+				if (arrayref->reflowerindexpr || arrayref->refassgnexpr)
+					type = arrayref->refarraytype;
+				else
+					type = arrayref->refelemtype;
+			}
 			break;
 		case T_FuncExpr:
 			type = ((FuncExpr *) expr)->funcresulttype;
@@ -1802,9 +1810,6 @@ exprType(Node *expr)
 		case T_CaseExpr:
 			type = ((CaseExpr *) expr)->casetype;
 			break;
-		case T_CaseWhen:
-			type = exprType((Node *) ((CaseWhen *) expr)->result);
-			break;
 		case T_CaseTestExpr:
 			type = ((CaseTestExpr *) expr)->typeId;
 			break;
@@ -1872,8 +1877,13 @@ exprTypmod(Node *expr)
 	{
 		case T_Var:
 			return ((Var *) expr)->vartypmod;
+		case T_Const:
+			return ((Const *) expr)->consttypmod;
 		case T_Param:
 			return ((Param *) expr)->paramtypmod;
+		case T_ArrayRef:
+			/* typmod is the same for array or element */
+			return ((ArrayRef *) expr)->reftypmod;
 		case T_FuncExpr:
 			{
 				int32		coercedTypmod;
@@ -1883,6 +1893,27 @@ exprTypmod(Node *expr)
 					return coercedTypmod;
 			}
 			break;
+		case T_SubLink:
+			{
+				SubLink    *sublink = (SubLink *) expr;
+
+				if (sublink->subLinkType == EXPR_SUBLINK ||
+					sublink->subLinkType == ARRAY_SUBLINK)
+				{
+					/* get the typmod of the subselect's first target column */
+					Query	   *qtree = (Query *) sublink->subselect;
+					TargetEntry *tent;
+
+					if (!qtree || !IsA(qtree, Query))
+						elog(ERROR, "cannot get type for untransformed sublink");
+					tent = (TargetEntry *) linitial(qtree->targetList);
+					Assert(IsA(tent, TargetEntry));
+					Assert(!tent->resjunk);
+					return exprTypmod((Node *) tent->expr);
+					/* note we don't need to care if it's an array */
+				}
+			}
+			break;
 		case T_FieldSelect:
 			return ((FieldSelect *) expr)->resulttypmod;
 		case T_RelabelType:
@@ -1920,6 +1951,34 @@ exprTypmod(Node *expr)
 			break;
 		case T_CaseTestExpr:
 			return ((CaseTestExpr *) expr)->typeMod;
+		case T_ArrayExpr:
+			{
+				/*
+				 * If all the elements agree on type/typmod, return that
+				 * typmod, else use -1
+				 */
+				ArrayExpr  *arrayexpr = (ArrayExpr *) expr;
+				Oid			arraytype = arrayexpr->array_typeid;
+				int32		typmod;
+				ListCell   *elem;
+
+				if (arrayexpr->elements == NIL)
+					return -1;
+				typmod = exprTypmod((Node *) linitial(arrayexpr->elements));
+				if (typmod < 0)
+					return -1;	/* no point in trying harder */
+				foreach(elem, arrayexpr->elements)
+				{
+					Node	   *e = (Node *) lfirst(elem);
+
+					if (exprType(e) != arraytype)
+						return -1;
+					if (exprTypmod(e) != typmod)
+						return -1;
+				}
+				return typmod;
+			}
+			break;
 		case T_CoalesceExpr:
 			{
 				/*

src/backend/parser/parse_node.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/parser/parse_node.c,v 1.96 2007/01/05 22:19:34 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/parser/parse_node.c,v 1.97 2007/03/17 00:11:04 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -153,7 +153,8 @@ transformArrayType(Oid arrayType)
  * arrayType	OID of array's datatype (should match type of arrayBase)
  * elementType	OID of array's element type (fetch with transformArrayType,
  *				or pass InvalidOid to do it here)
- * elementTypMod typmod to be applied to array elements (if storing)
+ * elementTypMod typmod to be applied to array elements (if storing) or of
+ *				the source array (if fetching)
  * indirection	Untransformed list of subscripts (must not be NIL)
  * assignFrom	NULL for array fetch, else transformed expression for source.
  */
@@ -166,7 +167,6 @@ transformArraySubscripts(ParseState *pstate,
 						 List *indirection,
 						 Node *assignFrom)
 {
-	Oid			resultType;
 	bool		isSlice = false;
 	List	   *upperIndexpr = NIL;
 	List	   *lowerIndexpr = NIL;
@@ -196,16 +196,6 @@ transformArraySubscripts(ParseState *pstate,
 		}
 	}
 
-	/*
-	 * The type represented by the subscript expression is the element type if
-	 * we are fetching a single element, but it is the same as the array type
-	 * if we are fetching a slice or storing.
-	 */
-	if (isSlice || assignFrom != NULL)
-		resultType = arrayType;
-	else
-		resultType = elementType;
-
 	/*
 	 * Transform the subscript expressions.
 	 */
@@ -235,6 +225,7 @@ transformArraySubscripts(ParseState *pstate,
 			{
 				/* Make a constant 1 */
 				subexpr = (Node *) makeConst(INT4OID,
+											 -1,
 											 sizeof(int32),
 											 Int32GetDatum(1),
 											 false,
@@ -284,9 +275,9 @@ transformArraySubscripts(ParseState *pstate,
 	 * Ready to build the ArrayRef node.
 	 */
 	aref = makeNode(ArrayRef);
-	aref->refrestype = resultType;
 	aref->refarraytype = arrayType;
 	aref->refelemtype = elementType;
+	aref->reftypmod = elementTypMod;
 	aref->refupperindexpr = upperIndexpr;
 	aref->reflowerindexpr = lowerIndexpr;
 	aref->refexpr = (Expr *) arrayBase;
@@ -399,6 +390,7 @@ make_const(Value *value)
 		case T_Null:
 			/* return a null const */
 			con = makeConst(UNKNOWNOID,
+							-1,
 							-2,
 							(Datum) 0,
 							true,
@@ -411,6 +403,7 @@ make_const(Value *value)
 	}
 
 	con = makeConst(typeid,
+					-1,			/* typmod -1 is OK for all cases */
 					typelen,
 					val,
 					false,

src/backend/rewrite/rewriteHandler.c

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/rewrite/rewriteHandler.c,v 1.171 2007/03/01 18:50:28 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/rewrite/rewriteHandler.c,v 1.172 2007/03/17 00:11:04 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -643,6 +643,7 @@ rewriteTargetList(Query *parsetree, Relation target_relation,
 				else
 				{
 					new_expr = (Node *) makeConst(att_tup->atttypid,
+												  -1,
 												  att_tup->attlen,
 												  (Datum) 0,
 												  true, /* isnull */
@@ -981,6 +982,7 @@ rewriteValuesRTE(RangeTblEntry *rte, Relation target_relation, List *attrnos)
 				if (!new_expr)
 				{
 					new_expr = (Node *) makeConst(att_tup->atttypid,
+												  -1,
 												  att_tup->attlen,
 												  (Datum) 0,
 												  true, /* isnull */

src/backend/utils/adt/ruleutils.c

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/ruleutils.c,v 1.253 2007/03/15 23:12:06 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/ruleutils.c,v 1.254 2007/03/17 00:11:05 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -170,7 +170,11 @@ static void get_oper_expr(OpExpr *expr, deparse_context *context);
 static void get_func_expr(FuncExpr *expr, deparse_context *context,
 			  bool showimplicit);
 static void get_agg_expr(Aggref *aggref, deparse_context *context);
-static void get_const_expr(Const *constval, deparse_context *context);
+static void get_coercion_expr(Node *arg, deparse_context *context,
+							  Oid resulttype, int32 resulttypmod,
+							  Node *parentNode);
+static void get_const_expr(Const *constval, deparse_context *context,
+						   bool showtype);
 static void get_sublink_expr(SubLink *sublink, deparse_context *context);
 static void get_from_clause(Query *query, const char *prefix,
 				deparse_context *context);
@@ -3364,7 +3368,7 @@ get_rule_expr(Node *node, deparse_context *context,
 			break;
 
 		case T_Const:
-			get_const_expr((Const *) node, context);
+			get_const_expr((Const *) node, context, true);
 			break;
 
 		case T_Param:
@@ -3576,14 +3580,10 @@ get_rule_expr(Node *node, deparse_context *context,
 				}
 				else
 				{
-					if (!PRETTY_PAREN(context))
-						appendStringInfoChar(buf, '(');
-					get_rule_expr_paren(arg, context, false, node);
-					if (!PRETTY_PAREN(context))
-						appendStringInfoChar(buf, ')');
-					appendStringInfo(buf, "::%s",
-								format_type_with_typemod(relabel->resulttype,
-													 relabel->resulttypmod));
+					get_coercion_expr(arg, context,
+									  relabel->resulttype,
+									  relabel->resulttypmod,
+									  node);
 				}
 			}
 			break;
@@ -3601,13 +3601,9 @@ get_rule_expr(Node *node, deparse_context *context,
 				}
 				else
 				{
-					if (!PRETTY_PAREN(context))
-						appendStringInfoChar(buf, '(');
-					get_rule_expr_paren(arg, context, false, node);
-					if (!PRETTY_PAREN(context))
-						appendStringInfoChar(buf, ')');
-					appendStringInfo(buf, "::%s",
-						  format_type_with_typemod(convert->resulttype, -1));
+					get_coercion_expr(arg, context,
+									  convert->resulttype, -1,
+									  node);
 				}
 			}
 			break;
@@ -4070,14 +4066,10 @@ get_rule_expr(Node *node, deparse_context *context,
 				}
 				else
 				{
-					if (!PRETTY_PAREN(context))
-						appendStringInfoChar(buf, '(');
-					get_rule_expr_paren(arg, context, false, node);
-					if (!PRETTY_PAREN(context))
-						appendStringInfoChar(buf, ')');
-					appendStringInfo(buf, "::%s",
-								  format_type_with_typemod(ctest->resulttype,
-													   ctest->resulttypmod));
+					get_coercion_expr(arg, context,
+									  ctest->resulttype,
+									  ctest->resulttypmod,
+									  node);
 				}
 			}
 			break;
@@ -4213,13 +4205,9 @@ get_func_expr(FuncExpr *expr, deparse_context *context,
 		/* Get the typmod if this is a length-coercion function */
 		(void) exprIsLengthCoercion((Node *) expr, &coercedTypmod);
 
-		if (!PRETTY_PAREN(context))
-			appendStringInfoChar(buf, '(');
-		get_rule_expr_paren(arg, context, false, (Node *) expr);
-		if (!PRETTY_PAREN(context))
-			appendStringInfoChar(buf, ')');
-		appendStringInfo(buf, "::%s",
-						 format_type_with_typemod(rettype, coercedTypmod));
+		get_coercion_expr(arg, context,
+						  rettype, coercedTypmod,
+						  (Node *) expr);
 
 		return;
 	}
@@ -4278,15 +4266,58 @@ get_agg_expr(Aggref *aggref, deparse_context *context)
 	appendStringInfoChar(buf, ')');
 }
 
+/* ----------
+ * get_coercion_expr
+ *
+ *	Make a string representation of a value coerced to a specific type
+ * ----------
+ */
+static void
+get_coercion_expr(Node *arg, deparse_context *context,
+				  Oid resulttype, int32 resulttypmod,
+				  Node *parentNode)
+{
+	StringInfo	buf = context->buf;
+
+	/*
+	 * Since parse_coerce.c doesn't immediately collapse application of
+	 * length-coercion functions to constants, what we'll typically see
+	 * in such cases is a Const with typmod -1 and a length-coercion
+	 * function right above it.  Avoid generating redundant output.
+	 * However, beware of suppressing casts when the user actually wrote
+	 * something like 'foo'::text::char(3).
+	 */
+	if (arg && IsA(arg, Const) &&
+		((Const *) arg)->consttype == resulttype &&
+		((Const *) arg)->consttypmod == -1)
+	{
+		/* Show the constant without normal ::typename decoration */
+		get_const_expr((Const *) arg, context, false);
+	}
+	else
+	{
+		if (!PRETTY_PAREN(context))
+			appendStringInfoChar(buf, '(');
+		get_rule_expr_paren(arg, context, false, parentNode);
+		if (!PRETTY_PAREN(context))
+			appendStringInfoChar(buf, ')');
+	}
+	appendStringInfo(buf, "::%s",
+					 format_type_with_typemod(resulttype, resulttypmod));
+}
 
 /* ----------
  * get_const_expr
  *
  *	Make a string representation of a Const
+ *
+ * Note: if showtype is false, the Const is the direct argument of a coercion
+ * operation with the same target type, and so we should suppress "::typename"
+ * to avoid redundant output.
  * ----------
  */
 static void
-get_const_expr(Const *constval, deparse_context *context)
+get_const_expr(Const *constval, deparse_context *context, bool showtype)
 {
 	StringInfo	buf = context->buf;
 	Oid			typoutput;
@@ -4302,8 +4333,11 @@ get_const_expr(Const *constval, deparse_context *context)
 		 * Always label the type of a NULL constant to prevent misdecisions
 		 * about type when reparsing.
 		 */
-		appendStringInfo(buf, "NULL::%s",
-						 format_type_with_typemod(constval->consttype, -1));
+		appendStringInfo(buf, "NULL");
+		if (showtype)
+			appendStringInfo(buf, "::%s",
+							 format_type_with_typemod(constval->consttype,
+													  constval->consttypmod));
 		return;
 	}
 
@@ -4376,6 +4410,9 @@ get_const_expr(Const *constval, deparse_context *context)
 
 	pfree(extval);
 
+	if (!showtype)
+		return;
+
 	/*
 	 * Append ::typename unless the constant will be implicitly typed as the
 	 * right type when it is read in.  XXX this code has to be kept in sync
@@ -4399,7 +4436,8 @@ get_const_expr(Const *constval, deparse_context *context)
 	}
 	if (needlabel)
 		appendStringInfo(buf, "::%s",
-						 format_type_with_typemod(constval->consttype, -1));
+						 format_type_with_typemod(constval->consttype,
+												  constval->consttypmod));
 }
 
 

src/backend/utils/adt/selfuncs.c

@@ -15,7 +15,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.228 2007/02/27 23:48:09 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.229 2007/03/17 00:11:05 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1599,6 +1599,7 @@ scalararraysel(PlannerInfo *root,
 
 			args = list_make2(leftop,
 							  makeConst(nominal_element_type,
+										-1,
 										elmlen,
 										elem_values[i],
 										elem_nulls[i],
@@ -4717,7 +4718,8 @@ string_to_const(const char *str, Oid datatype)
 {
 	Datum		conval = string_to_datum(str, datatype);
 
-	return makeConst(datatype, ((datatype == NAMEOID) ? NAMEDATALEN : -1),
+	return makeConst(datatype, -1,
+					 ((datatype == NAMEOID) ? NAMEDATALEN : -1),
 					 conval, false, false);
 }
 
@@ -4734,7 +4736,7 @@ string_to_bytea_const(const char *str, size_t str_len)
 	SET_VARSIZE(bstr, VARHDRSZ + str_len);
 	conval = PointerGetDatum(bstr);
 
-	return makeConst(BYTEAOID, -1, conval, false, false);
+	return makeConst(BYTEAOID, -1, -1, conval, false, false);
 }
 
 /*-------------------------------------------------------------------------

src/backend/utils/cache/lsyscache.c

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/cache/lsyscache.c,v 1.148 2007/02/14 01:58:57 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/cache/lsyscache.c,v 1.149 2007/03/17 00:11:05 tgl Exp $
  *
  * NOTES
  *	  Eventually, the index information should go through here, too.
@@ -1964,6 +1964,7 @@ get_typdefault(Oid typid)
 										 getTypeIOParam(typeTuple), -1);
 			/* Build a Const node containing the value */
 			expr = (Node *) makeConst(typid,
+									  -1,
 									  type->typlen,
 									  datum,
 									  false,

src/include/catalog/catversion.h

@@ -37,7 +37,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.390 2007/03/16 17:57:36 mha Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.391 2007/03/17 00:11:05 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	200703161
+#define CATALOG_VERSION_NO	200703162
 
 #endif

src/include/nodes/makefuncs.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/nodes/makefuncs.h,v 1.57 2007/01/05 22:19:55 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/nodes/makefuncs.h,v 1.58 2007/03/17 00:11:05 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -37,6 +37,7 @@ extern TargetEntry *makeTargetEntry(Expr *expr,
 extern TargetEntry *flatCopyTargetEntry(TargetEntry *src_tle);
 
 extern Const *makeConst(Oid consttype,
+		  int32 consttypmod,
 		  int constlen,
 		  Datum constvalue,
 		  bool constisnull,

src/include/nodes/primnodes.h

@@ -10,7 +10,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/nodes/primnodes.h,v 1.127 2007/02/22 22:00:25 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/nodes/primnodes.h,v 1.128 2007/03/17 00:11:05 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -154,7 +154,8 @@ typedef struct Var
 typedef struct Const
 {
 	Expr		xpr;
-	Oid			consttype;		/* PG_TYPE OID of the constant's datatype */
+	Oid			consttype;		/* pg_type OID of the constant's datatype */
+	int32		consttypmod;	/* typmod value, if any */
 	int			constlen;		/* typlen of the constant's datatype */
 	Datum		constvalue;		/* the constant's value */
 	bool		constisnull;	/* whether the constant is null (if true,
@@ -236,17 +237,17 @@ typedef struct Aggref
  * reflowerindexpr must be the same length as refupperindexpr when it
  * is not NIL.
  *
- * Note: refrestype is NOT the element type, but the array type,
- * when doing subarray fetch or either type of store.
+ * Note: the result datatype is the element type when fetching a single
+ * element; but it is the array type when doing subarray fetch or either
+ * type of store.
  * ----------------
  */
 typedef struct ArrayRef
 {
 	Expr		xpr;
-	Oid			refrestype;		/* type of the result of the ArrayRef
-								 * operation */
 	Oid			refarraytype;	/* type of the array proper */
 	Oid			refelemtype;	/* type of the array elements */
+	int32		reftypmod;		/* typmod of the array (and elements too) */
 	List	   *refupperindexpr;/* expressions that evaluate to upper array
 								 * indexes */
 	List	   *reflowerindexpr;/* expressions that evaluate to lower array