Changed ExecConstraints() and ExecRelCheck() to cache the constraints

qualification expression trees in the execution state. Prevents from
memory exhaustion on INSERT, UPDATE or COPY to tables that have CHECK
constraints. Speedup against the variant using freeObject() is more than
factor 2.

Jan

src/backend/commands/copy.c

@@ -6,7 +6,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/commands/copy.c,v 1.71 1999/02/03 21:16:03 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/commands/copy.c,v 1.72 1999/02/07 16:17:10 wieck Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -505,6 +505,7 @@ CopyFrom(Relation rel, bool binary, bool oids, FILE *fp, char *delim)
 	Node	  **indexPred = NULL;
 	TupleDesc	rtupdesc;
 	ExprContext *econtext = NULL;
+	EState		*estate = makeNode(EState);	/* for ExecConstraints() */
 
 #ifndef OMIT_PARTIAL_INDEX
 	TupleTable	tupleTable;
@@ -805,7 +806,7 @@ CopyFrom(Relation rel, bool binary, bool oids, FILE *fp, char *delim)
 			 */
 
 			if (rel->rd_att->constr)
-				ExecConstraints("CopyFrom", rel, tuple);
+				ExecConstraints("CopyFrom", rel, tuple, estate);
 
 			heap_insert(rel, tuple);
 

src/backend/executor/execMain.c

@@ -26,7 +26,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/executor/execMain.c,v 1.74 1999/02/07 14:20:11 wieck Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/executor/execMain.c,v 1.75 1999/02/07 16:17:11 wieck Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1124,7 +1124,7 @@ ExecAppend(TupleTableSlot *slot,
 
 	if (resultRelationDesc->rd_att->constr)
 	{
-		ExecConstraints("ExecAppend", resultRelationDesc, tuple);
+		ExecConstraints("ExecAppend", resultRelationDesc, tuple, estate);
 	}
 
 	/******************
@@ -1327,7 +1327,7 @@ ExecReplace(TupleTableSlot *slot,
 
 	if (resultRelationDesc->rd_att->constr)
 	{
-		ExecConstraints("ExecReplace", resultRelationDesc, tuple);
+		ExecConstraints("ExecReplace", resultRelationDesc, tuple, estate);
 	}
 
 	/*
@@ -1472,7 +1472,7 @@ ExecAttrDefault(Relation rel, HeapTuple tuple)
 #endif
 
 static char *
-ExecRelCheck(Relation rel, HeapTuple tuple)
+ExecRelCheck(Relation rel, HeapTuple tuple, EState *estate)
 {
 	int			ncheck = rel->rd_att->constr->num_check;
 	ConstrCheck *check = rel->rd_att->constr->check;
@@ -1505,14 +1505,24 @@ ExecRelCheck(Relation rel, HeapTuple tuple)
 	econtext->ecxt_param_exec_vals = NULL;		/* exec param values */
 	econtext->ecxt_range_table = rtlist;		/* range table */
 
+	if (estate->es_result_relation_constraints == NULL)
+	{
+		estate->es_result_relation_constraints =
+				(List **)palloc(ncheck * sizeof(List *));
+
+		for (i = 0; i < ncheck; i++)
+		{
+			qual = (List *) stringToNode(check[i].ccbin);
+			estate->es_result_relation_constraints[i] = qual;
+		}
+	}
+
 	for (i = 0; i < ncheck; i++)
 	{
-		qual = (List *) stringToNode(check[i].ccbin);
+		qual = estate->es_result_relation_constraints[i];
 
 		res = ExecQual(qual, econtext);
 
-		freeObject(qual);
-
 		if (!res)
 			return check[i].ccname;
 	}
@@ -1528,7 +1538,7 @@ ExecRelCheck(Relation rel, HeapTuple tuple)
 }
 
 void
-ExecConstraints(char *caller, Relation rel, HeapTuple tuple)
+ExecConstraints(char *caller, Relation rel, HeapTuple tuple, EState *estate)
 {
 
 	Assert(rel->rd_att->constr);
@@ -1549,7 +1559,7 @@ ExecConstraints(char *caller, Relation rel, HeapTuple tuple)
 	{
 		char	   *failed;
 
-		if ((failed = ExecRelCheck(rel, tuple)) != NULL)
+		if ((failed = ExecRelCheck(rel, tuple, estate)) != NULL)
 			elog(ERROR, "%s: rejected due to CHECK constraint %s", caller, failed);
 	}
 

src/include/executor/executor.h

@@ -6,7 +6,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: executor.h,v 1.28 1998/11/27 19:33:32 vadim Exp $
+ * $Id: executor.h,v 1.29 1999/02/07 16:17:12 wieck Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -85,7 +85,8 @@ extern HeapTuple ExecRemoveJunk(JunkFilter *junkfilter, TupleTableSlot *slot);
 extern TupleDesc ExecutorStart(QueryDesc *queryDesc, EState *estate);
 extern TupleTableSlot *ExecutorRun(QueryDesc *queryDesc, EState *estate, int feature, int count);
 extern void ExecutorEnd(QueryDesc *queryDesc, EState *estate);
-extern void ExecConstraints(char *caller, Relation rel, HeapTuple tuple);
+extern void ExecConstraints(char *caller, Relation rel, HeapTuple tuple, 
+											EState *estate);
 #ifdef QUERY_LIMIT
 extern int ExecutorLimit(int limit);
 extern int ExecutorGetLimit(void);

src/include/nodes/execnodes.h

@@ -6,7 +6,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: execnodes.h,v 1.22 1999/01/29 09:23:13 vadim Exp $
+ * $Id: execnodes.h,v 1.23 1999/02/07 16:17:14 wieck Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -199,6 +199,7 @@ typedef struct EState
 	Snapshot		es_snapshot;
 	List		   *es_range_table;
 	RelationInfo   *es_result_relation_info;
+	List		  **es_result_relation_constraints;
 	Relation		es_into_relation_descriptor;
 	ParamListInfo	es_param_list_info;
 	ParamExecData  *es_param_exec_vals;	/* this is for subselects */