Improve the plan cache invalidation mechanism to make it invalidate plans

when user-defined functions used in a plan are modified.  Also invalidate
plans when schemas, operators, or operator classes are modified; but for these
cases we just invalidate everything rather than tracking exact dependencies,
since these types of objects seldom change in a production database.

Tom Lane; loosely based on a patch by Martin Pihlak.

Author: tglsfdc

src/backend/catalog/namespace.c

@@ -13,7 +13,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/catalog/namespace.c,v 1.111 2008/09/01 20:42:43 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/catalog/namespace.c,v 1.112 2008/09/09 18:58:08 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -187,7 +187,7 @@ static void recomputeNamespacePath(void);
 static void InitTempTableNamespace(void);
 static void RemoveTempRelations(Oid tempNamespaceId);
 static void RemoveTempRelationsCallback(int code, Datum arg);
-static void NamespaceCallback(Datum arg, Oid relid);
+static void NamespaceCallback(Datum arg, int cacheid, ItemPointer tuplePtr);
 
 /* These don't really need to appear in any header file */
 Datum		pg_table_is_visible(PG_FUNCTION_ARGS);
@@ -3094,7 +3094,7 @@ InitializeSearchPath(void)
  *		Syscache inval callback function
  */
 static void
-NamespaceCallback(Datum arg, Oid relid)
+NamespaceCallback(Datum arg, int cacheid, ItemPointer tuplePtr)
 {
 	/* Force search path to be recomputed on next use */
 	baseSearchPathValid = false;

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 1.404 2008/09/01 20:42:44 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/nodes/copyfuncs.c,v 1.405 2008/09/09 18:58:08 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -88,6 +88,7 @@ _copyPlannedStmt(PlannedStmt *from)
 	COPY_NODE_FIELD(returningLists);
 	COPY_NODE_FIELD(rowMarks);
 	COPY_NODE_FIELD(relationOids);
+	COPY_NODE_FIELD(invalItems);
 	COPY_SCALAR_FIELD(nParamExec);
 
 	return newnode;
@@ -689,6 +690,21 @@ _copyLimit(Limit *from)
 	return newnode;
 }
 
+/*
+ * _copyPlanInvalItem
+ */
+static PlanInvalItem *
+_copyPlanInvalItem(PlanInvalItem *from)
+{
+	PlanInvalItem *newnode = makeNode(PlanInvalItem);
+
+	COPY_SCALAR_FIELD(cacheId);
+	/* tupleId isn't really a "scalar", but this works anyway */
+	COPY_SCALAR_FIELD(tupleId);
+
+	return newnode;
+}
+
 /* ****************************************************************
  *					   primnodes.h copy functions
  * ****************************************************************
@@ -3157,6 +3173,9 @@ copyObject(void *from)
 		case T_Limit:
 			retval = _copyLimit(from);
 			break;
+		case T_PlanInvalItem:
+			retval = _copyPlanInvalItem(from);
+			break;
 
 			/*
 			 * PRIMITIVE NODES

src/backend/nodes/outfuncs.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/nodes/outfuncs.c,v 1.338 2008/09/01 20:42:44 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/nodes/outfuncs.c,v 1.339 2008/09/09 18:58:08 tgl Exp $
  *
  * NOTES
  *	  Every node type that can appear in stored rules' parsetrees *must*
@@ -255,6 +255,7 @@ _outPlannedStmt(StringInfo str, PlannedStmt *node)
 	WRITE_NODE_FIELD(returningLists);
 	WRITE_NODE_FIELD(rowMarks);
 	WRITE_NODE_FIELD(relationOids);
+	WRITE_NODE_FIELD(invalItems);
 	WRITE_INT_FIELD(nParamExec);
 }
 
@@ -593,6 +594,14 @@ _outUnique(StringInfo str, Unique *node)
 		appendStringInfo(str, " %u", node->uniqOperators[i]);
 }
 
+static void
+_outHash(StringInfo str, Hash *node)
+{
+	WRITE_NODE_TYPE("HASH");
+
+	_outPlanInfo(str, (Plan *) node);
+}
+
 static void
 _outSetOp(StringInfo str, SetOp *node)
 {
@@ -631,11 +640,14 @@ _outLimit(StringInfo str, Limit *node)
 }
 
 static void
-_outHash(StringInfo str, Hash *node)
+_outPlanInvalItem(StringInfo str, PlanInvalItem *node)
 {
-	WRITE_NODE_TYPE("HASH");
+	WRITE_NODE_TYPE("PLANINVALITEM");
 
-	_outPlanInfo(str, (Plan *) node);
+	WRITE_INT_FIELD(cacheId);
+	appendStringInfo(str, " :tupleId (%u,%u)",
+					 ItemPointerGetBlockNumber(&node->tupleId),
+					 ItemPointerGetOffsetNumber(&node->tupleId));
 }
 
 /*****************************************************************************
@@ -1354,6 +1366,7 @@ _outPlannerGlobal(StringInfo str, PlannerGlobal *node)
 	WRITE_BITMAPSET_FIELD(rewindPlanIDs);
 	WRITE_NODE_FIELD(finalrtable);
 	WRITE_NODE_FIELD(relationOids);
+	WRITE_NODE_FIELD(invalItems);
 }
 
 static void
@@ -2206,14 +2219,17 @@ _outNode(StringInfo str, void *obj)
 			case T_Unique:
 				_outUnique(str, obj);
 				break;
+			case T_Hash:
+				_outHash(str, obj);
+				break;
 			case T_SetOp:
 				_outSetOp(str, obj);
 				break;
 			case T_Limit:
 				_outLimit(str, obj);
 				break;
-			case T_Hash:
-				_outHash(str, obj);
+			case T_PlanInvalItem:
+				_outPlanInvalItem(str, obj);
 				break;
 			case T_Alias:
 				_outAlias(str, obj);

src/backend/optimizer/plan/planner.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/plan/planner.c,v 1.242 2008/08/17 01:19:59 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/plan/planner.c,v 1.243 2008/09/09 18:58:08 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -140,6 +140,7 @@ standard_planner(Query *parse, int cursorOptions, ParamListInfo boundParams)
 	glob->rewindPlanIDs = NULL;
 	glob->finalrtable = NIL;
 	glob->relationOids = NIL;
+	glob->invalItems = NIL;
 	glob->transientPlan = false;
 
 	/* Determine what fraction of the plan is likely to be scanned */
@@ -213,6 +214,7 @@ standard_planner(Query *parse, int cursorOptions, ParamListInfo boundParams)
 	result->returningLists = root->returningLists;
 	result->rowMarks = parse->rowMarks;
 	result->relationOids = glob->relationOids;
+	result->invalItems = glob->invalItems;
 	result->nParamExec = list_length(glob->paramlist);
 
 	return result;