Add support for the CASE statement in the rewrite handling.

Allows (at least some) rules and views.
Still some trouble (crashes) with target CASE columns spanning tables,
 but lots now works.

src/backend/nodes/outfuncs.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/nodes/outfuncs.c,v 1.49 1998/12/04 15:33:33 thomas Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/nodes/outfuncs.c,v 1.50 1998/12/14 00:01:47 thomas Exp $
  *
  * NOTES
  *	  Every (plan) node in POSTGRES has an associated "out" routine which
@@ -1702,7 +1702,7 @@ _outCaseWhen(StringInfo str, CaseWhen *node)
 {
 	char		buf[500];
 
-	sprintf(buf, " :when ");
+	sprintf(buf, " WHEN ");
 	appendStringInfo(str, buf);
 	_outNode(str, node->expr);
 	sprintf(buf, " :then ");

src/backend/nodes/readfuncs.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/nodes/readfuncs.c,v 1.39 1998/11/22 10:48:40 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/nodes/readfuncs.c,v 1.40 1998/12/14 00:01:47 thomas Exp $
  *
  * NOTES
  *	  Most of the read functions for plan nodes are tested. (In fact, they
@@ -786,6 +786,50 @@ _readExpr()
 	return local_node;
 }
 
+/* ----------------
+ *		_readCaseExpr
+ *
+ *	CaseExpr is a subclass of Node
+ * ----------------
+ */
+static CaseExpr *
+_readCaseExpr()
+{
+	CaseExpr   *local_node;
+	char	   *token;
+	int			length;
+
+	local_node = makeNode(CaseExpr);
+
+	local_node->args = nodeRead(true);
+	token = lsptok(NULL, &length);		/* eat :default */
+	local_node->defresult = nodeRead(true);
+
+	return local_node;
+}
+
+/* ----------------
+ *		_readCaseWhen
+ *
+ *	CaseWhen is a subclass of Node
+ * ----------------
+ */
+static CaseWhen *
+_readCaseWhen()
+{
+	CaseWhen   *local_node;
+	char	   *token;
+	int			length;
+
+	local_node = makeNode(CaseWhen);
+
+	local_node->expr = nodeRead(true);
+	token = lsptok(NULL, &length);		/* eat :then */
+	local_node->result = nodeRead(true);
+
+	return local_node;
+}
+
 /* ----------------
  *		_readVar
  *
@@ -2037,6 +2081,10 @@ parsePlanString(void)
 		return_value = _readSortClause();
 	else if (!strncmp(token, "GROUPCLAUSE", length))
 		return_value = _readGroupClause();
+	else if (!strncmp(token, "CASE", length))
+		return_value = _readCaseExpr();
+	else if (!strncmp(token, "WHEN", length))
+		return_value = _readCaseWhen();
 	else
 		elog(ERROR, "badly formatted planstring \"%.10s\"...\n", token);
 

src/backend/optimizer/plan/setrefs.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/optimizer/plan/setrefs.c,v 1.28 1998/10/08 18:29:29 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/optimizer/plan/setrefs.c,v 1.29 1998/12/14 00:02:10 thomas Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -303,7 +303,7 @@ replace_clause_joinvar_refs(Expr *clause,
 	{
 		temp = (List *) replace_joinvar_refs((Var *) clause,
 											 outer_tlist, inner_tlist);
-		if (temp)
+		if (temp != NULL)
 			return temp;
 		else if (clause != NULL)
 			return (List *) clause;
@@ -402,6 +402,33 @@ replace_clause_joinvar_refs(Expr *clause,
 										   inner_tlist);
 		return (List *) clause;
 	}
+	else if (IsA(clause, CaseExpr))
+	{
+		((CaseExpr *) clause)->args =
+			(List *) replace_subclause_joinvar_refs(((CaseExpr *) clause)->args,
+													outer_tlist,
+													inner_tlist);
+
+		((CaseExpr *) clause)->defresult =
+			(Node *) replace_clause_joinvar_refs((Expr *) ((CaseExpr *) clause)->defresult,
+												 outer_tlist,
+												 inner_tlist);
+		return (List *) clause;
+	}
+	else if (IsA(clause, CaseWhen))
+	{
+		((CaseWhen *) clause)->expr =
+			(Node *) replace_clause_joinvar_refs((Expr *) ((CaseWhen *) clause)->expr,
+												 outer_tlist,
+												 inner_tlist);
+
+		((CaseWhen *) clause)->result =
+			(Node *) replace_clause_joinvar_refs((Expr *) ((CaseWhen *) clause)->result,
+												 outer_tlist,
+												 inner_tlist);
+		return (List *) clause;
+	}
+
 	/* shouldn't reach here */
 	elog(ERROR, "replace_clause_joinvar_refs: unsupported clause %d",
 		 nodeTag(clause));

src/backend/rewrite/rewriteHandler.c

@@ -6,7 +6,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteHandler.c,v 1.26 1998/12/04 15:34:36 thomas Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteHandler.c,v 1.27 1998/12/14 00:02:16 thomas Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1457,6 +1457,34 @@ apply_RIR_adjust_sublevel(Node *node, int sublevels_up)
 			}
 			break;
 
+		case T_CaseExpr:
+			{
+				CaseExpr	*exp = (CaseExpr *)node;
+
+				apply_RIR_adjust_sublevel(
+						(Node *)(exp->args),
+						sublevels_up);
+
+				apply_RIR_adjust_sublevel(
+						(Node *)(exp->defresult),
+						sublevels_up);
+			}
+			break;
+
+		case T_CaseWhen:
+			{
+				CaseWhen	*exp = (CaseWhen *)node;
+
+				apply_RIR_adjust_sublevel(
+						(Node *)(exp->expr),
+						sublevels_up);
+
+				apply_RIR_adjust_sublevel(
+						(Node *)(exp->result),
+						sublevels_up);
+			}
+			break;
+
 		default:
 			elog(NOTICE, "unknown node tag %d in attribute_used()", nodeTag(node));
 			elog(NOTICE, "Node is: %s", nodeToString(node));
@@ -1691,6 +1719,50 @@ apply_RIR_view(Node **nodePtr, int rt_index, RangeTblEntry *rte, List *tlist, in
 			}
 			break;
 
+		case T_CaseExpr:
+			{
+				CaseExpr	*exp = (CaseExpr *)node;
+
+				apply_RIR_view(
+						(Node **)(&(exp->args)),
+						rt_index,
+						rte,
+						tlist,
+						modified,
+						sublevels_up);
+
+				apply_RIR_view(
+						(Node **)(&(exp->defresult)),
+						rt_index,
+						rte,
+						tlist,
+						modified,
+						sublevels_up);
+			}
+			break;
+
+		case T_CaseWhen:
+			{
+				CaseWhen	*exp = (CaseWhen *)node;
+
+				apply_RIR_view(
+						(Node **)(&(exp->expr)),
+						rt_index,
+						rte,
+						tlist,
+						modified,
+						sublevels_up);
+
+				apply_RIR_view(
+						(Node **)(&(exp->result)),
+						rt_index,
+						rte,
+						tlist,
+						modified,
+						sublevels_up);
+			}
+			break;
+
 		default:
 			elog(NOTICE, "unknown node tag %d in apply_RIR_view()", nodeTag(node));
 			elog(NOTICE, "Node is: %s", nodeToString(node));
@@ -1885,7 +1957,27 @@ fireRIRonSubselect(Node *node)
 			break;
 
 		case T_CaseExpr:
+			{
+				CaseExpr	*exp = (CaseExpr *)node;
+
+				fireRIRonSubselect(
+						(Node *)(exp->args));
+
+				fireRIRonSubselect(
+						(Node *)(exp->defresult));
+			}
+			break;
+
 		case T_CaseWhen:
+			{
+				CaseWhen	*exp = (CaseWhen *)node;
+
+				fireRIRonSubselect(
+						(Node *)(exp->expr));
+
+				fireRIRonSubselect(
+						(Node *)(exp->result));
+			}
 			break;
 
 		case T_Query:

src/backend/rewrite/rewriteManip.c

@@ -6,7 +6,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteManip.c,v 1.22 1998/10/21 16:21:26 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteManip.c,v 1.23 1998/12/14 00:02:17 thomas Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -191,6 +191,38 @@ OffsetVarNodes(Node *node, int offset, int sublevels_up)
 			}
 			break;
 
+		case T_CaseExpr:
+			{
+				CaseExpr	*exp = (CaseExpr *)node;
+
+				OffsetVarNodes(
+						(Node *)(exp->args),
+						offset,
+						sublevels_up);
+
+				OffsetVarNodes(
+						(Node *)(exp->defresult),
+						offset,
+						sublevels_up);
+			}
+			break;
+
+		case T_CaseWhen:
+			{
+				CaseWhen	*exp = (CaseWhen *)node;
+
+				OffsetVarNodes(
+						(Node *)(exp->expr),
+						offset,
+						sublevels_up);
+
+				OffsetVarNodes(
+						(Node *)(exp->result),
+						offset,
+						sublevels_up);
+			}
+			break;
+
 		default:
 			elog(NOTICE, "unknown node tag %d in OffsetVarNodes()", nodeTag(node));
 			elog(NOTICE, "Node is: %s", nodeToString(node));
@@ -377,6 +409,42 @@ ChangeVarNodes(Node *node, int rt_index, int new_index, int sublevels_up)
 			}
 			break;
 
+		case T_CaseExpr:
+			{
+				CaseExpr	*exp = (CaseExpr *)node;
+
+				ChangeVarNodes(
+						(Node *)(exp->args),
+						rt_index,
+						new_index,
+						sublevels_up);
+
+				ChangeVarNodes(
+						(Node *)(exp->defresult),
+						rt_index,
+						new_index,
+						sublevels_up);
+			}
+			break;
+
+		case T_CaseWhen:
+			{
+				CaseWhen	*exp = (CaseWhen *)node;
+
+				ChangeVarNodes(
+						(Node *)(exp->expr),
+						rt_index,
+						new_index,
+						sublevels_up);
+
+				ChangeVarNodes(
+						(Node *)(exp->result),
+						rt_index,
+						new_index,
+						sublevels_up);
+			}
+			break;
+
 		default:
 			elog(NOTICE, "unknown node tag %d in ChangeVarNodes()", nodeTag(node));
 			elog(NOTICE, "Node is: %s", nodeToString(node));

src/backend/rewrite/rewriteRemove.c

@@ -7,11 +7,13 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteRemove.c,v 1.19 1998/11/27 19:52:17 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteRemove.c,v 1.20 1998/12/14 00:02:17 thomas Exp $
  *
  *-------------------------------------------------------------------------
  */
 
+#include <string.h>
+
 #include "postgres.h"
 
 #include "fmgr.h"				/* for F_NAMEEQ */
@@ -39,14 +41,14 @@ RewriteGetRuleEventRel(char *rulename)
 							   PointerGetDatum(rulename),
 							   0, 0, 0);
 	if (!HeapTupleIsValid(htup))
-		elog(ERROR, "RewriteGetRuleEventRel: rule \"%s\" not found",
+		elog(ERROR, "Rule or view '%s' not found",
-			 rulename);
+			 ((!strncmp(rulename, "_RET", 4))? (rulename+4): rulename));
 	eventrel = ((Form_pg_rewrite) GETSTRUCT(htup))->ev_class;
 	htup = SearchSysCacheTuple(RELOID,
 							   PointerGetDatum(eventrel),
 							   0, 0, 0);
 	if (!HeapTupleIsValid(htup))
-		elog(ERROR, "RewriteGetRuleEventRel: class %d not found",
+		elog(ERROR, "Class '%d' not found",
 			 eventrel);
 	return ((Form_pg_class) GETSTRUCT(htup))->relname.data;
 }
@@ -94,7 +96,7 @@ RemoveRewriteRule(char *ruleName)
 	if (!HeapTupleIsValid(tuple))
 	{
 		heap_close(RewriteRelation);
-		elog(ERROR, "No rule with name = '%s' was found.\n", ruleName);
+		elog(ERROR, "Rule '%s' not found\n", ruleName);
 	}
 
 	/*
@@ -110,7 +112,7 @@ RemoveRewriteRule(char *ruleName)
 	{
 		/* XXX strange!!! */
 		pfree(tuple);
-		elog(ERROR, "RemoveRewriteRule: null event target relation!");
+		elog(ERROR, "RemoveRewriteRule: internal error; null event target relation!");
 	}
 	eventRelationOid = DatumGetObjectId(eventRelationOidDatum);