READ COMMITTED isolevel is implemented and is default now.

src/backend/access/heap/heapam.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.39 1998/12/15 12:45:13 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.40 1999/01/29 09:22:51 vadim Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -1373,6 +1373,7 @@ l3:
 	if (result != HeapTupleMayBeUpdated)
 	{
 		Assert(result == HeapTupleSelfUpdated || result == HeapTupleUpdated);
+		tuple->t_self = tuple->t_data->t_ctid;
 		LockBuffer(*buffer, BUFFER_LOCK_UNLOCK);
 		return result;
 	}

src/backend/access/nbtree/nbtinsert.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.32 1998/12/15 12:45:20 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.33 1999/01/29 09:22:52 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -134,6 +134,7 @@ l1:
 					 * If this tuple is being updated by other transaction
 					 * then we have to wait for its commit/abort.
 					 */
+					ReleaseBuffer(buffer);
 					if (TransactionIdIsValid(xwait))
 					{
 						if (nbuf != InvalidBuffer)

src/backend/access/transam/xact.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/transam/xact.c,v 1.28 1998/12/18 09:10:18 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/transam/xact.c,v 1.29 1999/01/29 09:22:53 vadim Exp $
  *
  * NOTES
  *		Transaction aborts can now occur two ways:
@@ -194,7 +194,7 @@ TransactionStateData CurrentTransactionStateData = {
 TransactionState CurrentTransactionState =
 &CurrentTransactionStateData;
 
-int	DefaultXactIsoLevel = XACT_SERIALIZABLE;
+int	DefaultXactIsoLevel = XACT_READ_COMMITTED;
 int	XactIsoLevel;
 
 /* ----------------

src/backend/commands/trigger.c

@@ -28,6 +28,7 @@
 #include "utils/inval.h"
 #include "utils/builtins.h"
 #include "utils/syscache.h"
+#include "executor/executor.h"
 
 #ifndef NO_SECURITY
 #include "miscadmin.h"
@@ -790,6 +791,8 @@ ExecARUpdateTriggers(EState *estate, ItemPointer tupleid, HeapTuple newtuple)
 	return;
 }
 
+extern	TupleTableSlot *EvalPlanQual(EState *estate, Index rti, ItemPointer tid);
+
 static HeapTuple
 GetTupleForTrigger(EState *estate, ItemPointer tid, bool before)
 {
@@ -806,6 +809,7 @@ GetTupleForTrigger(EState *estate, ItemPointer tid, bool before)
 		 *	mark tuple for update
 		 */
 		tuple.t_self = *tid;
+ltrmark:;
 		test = heap_mark4update(relation, &tuple, &buffer);
 		switch (test)
 		{
@@ -820,8 +824,23 @@ GetTupleForTrigger(EState *estate, ItemPointer tid, bool before)
 				ReleaseBuffer(buffer);
 				if (XactIsoLevel == XACT_SERIALIZABLE)
 					elog(ERROR, "Can't serialize access due to concurrent update");
-				else
-					elog(ERROR, "Isolation level %u is not supported", XactIsoLevel);
+				else if (!(ItemPointerEquals(&(tuple.t_self), tid)))
+				{
+					TupleTableSlot *slot = EvalPlanQual(estate, 
+						estate->es_result_relation_info->ri_RangeTableIndex, 
+						&(tuple.t_self));
+
+					if (!(TupIsNull(slot)))
+					{
+						*tid = tuple.t_self;
+						goto ltrmark;
+					}
+				}
+				/* 
+				 * if tuple was deleted or PlanQual failed
+				 * for updated tuple - we have not process
+				 * this tuple!
+				 */
 				return(NULL);
 
 			default:

src/backend/executor/nodeIndexscan.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/executor/nodeIndexscan.c,v 1.29 1998/11/27 19:52:03 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/executor/nodeIndexscan.c,v 1.30 1999/01/29 09:22:58 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -109,6 +109,40 @@ IndexNext(IndexScan *node)
 	heapRelation = scanstate->css_currentRelation;
 	numIndices = indexstate->iss_NumIndices;
 	slot = scanstate->css_ScanTupleSlot;
+
+	/*
+	 * Check if we are evaluating PlanQual for tuple of this relation.
+	 * Additional checking is not good, but no other way for now.
+	 * We could introduce new nodes for this case and handle
+	 * IndexScan --> NewNode switching in Init/ReScan plan...
+	 */
+	if (estate->es_evTuple != NULL && 
+		estate->es_evTuple[node->scan.scanrelid - 1] != NULL)
+	{
+		int		iptr;
+
+		slot->ttc_buffer = InvalidBuffer;
+		slot->ttc_shouldFree = false;
+		if (estate->es_evTupleNull[node->scan.scanrelid - 1])
+		{
+			slot->val = NULL;	/* must not free tuple! */
+			return (slot);
+		}
+		slot->val = estate->es_evTuple[node->scan.scanrelid - 1];
+		for (iptr = 0; iptr < numIndices; iptr++)
+		{
+			scanstate->cstate.cs_ExprContext->ecxt_scantuple = slot;
+			if (ExecQual(nth(iptr, node->indxqualorig),
+						 scanstate->cstate.cs_ExprContext))
+				break;
+		}
+		if (iptr == numIndices)	/* would not be returned by indices */
+			slot->val = NULL;
+		/* Flag for the next call that no more tuples */
+		estate->es_evTupleNull[node->scan.scanrelid - 1] = true;
+		return (slot);
+	}
+
 	tuple = &(indexstate->iss_htup);
 
 	/* ----------------
@@ -262,6 +296,14 @@ ExecIndexReScan(IndexScan *node, ExprContext *exprCtxt, Plan *parent)
 	numScanKeys = indexstate->iss_NumScanKeys;
 	indexstate->iss_IndexPtr = 0;
 
+	/* If this is re-scanning of PlanQual ... */
+	if (estate->es_evTuple != NULL && 
+		estate->es_evTuple[node->scan.scanrelid - 1] != NULL)
+	{
+		estate->es_evTupleNull[node->scan.scanrelid - 1] = false;
+		return;
+	}
+
 	/* it's possible in subselects */
 	if (exprCtxt == NULL)
 		exprCtxt = node->scan.scanstate->cstate.cs_ExprContext;

src/backend/executor/nodeSeqscan.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/executor/nodeSeqscan.c,v 1.15 1998/09/25 13:38:32 thomas Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/executor/nodeSeqscan.c,v 1.16 1999/01/29 09:22:58 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -64,6 +64,34 @@ SeqNext(SeqScan *node)
 	scanstate = node->scanstate;
 	scandesc = scanstate->css_currentScanDesc;
 	direction = estate->es_direction;
+	slot = scanstate->css_ScanTupleSlot;
+
+	/*
+	 * Check if we are evaluating PlanQual for tuple of this relation.
+	 * Additional checking is not good, but no other way for now.
+	 * We could introduce new nodes for this case and handle
+	 * SeqScan --> NewNode switching in Init/ReScan plan...
+	 */
+	if (estate->es_evTuple != NULL && 
+		estate->es_evTuple[node->scanrelid - 1] != NULL)
+	{
+		slot->ttc_buffer = InvalidBuffer;
+		slot->ttc_shouldFree = false;
+		if (estate->es_evTupleNull[node->scanrelid - 1])
+		{
+			slot->val = NULL;	/* must not free tuple! */
+			return (slot);
+		}
+		slot->val = estate->es_evTuple[node->scanrelid - 1];
+		/*
+		 * Note that unlike IndexScan, SeqScan never use keys
+		 * in heap_beginscan (and this is very bad) - so, here
+		 * we have not check are keys ok or not.
+		 */
+		/* Flag for the next call that no more tuples */
+		estate->es_evTupleNull[node->scanrelid - 1] = true;
+		return (slot);
+	}
 
 	/* ----------------
 	 *	get the next tuple from the access methods
@@ -79,7 +107,6 @@ SeqNext(SeqScan *node)
 	 *	be pfree()'d.
 	 * ----------------
 	 */
-	slot = scanstate->css_ScanTupleSlot;
 
 	slot = ExecStoreTuple(tuple,/* tuple to store */
 						  slot, /* slot to store in */
@@ -374,9 +401,15 @@ ExecSeqReScan(SeqScan *node, ExprContext *exprCtxt, Plan *parent)
 		outerPlan = outerPlan((Plan *) node);
 		ExecReScan(outerPlan, exprCtxt, parent);
 	}
-	else
+	else	/* otherwise, we are scanning a relation */
 	{
-		/* otherwise, we are scanning a relation */
+		/* If this is re-scanning of PlanQual ... */
+		if (estate->es_evTuple != NULL && 
+			estate->es_evTuple[node->scanrelid - 1] != NULL)
+		{
+			estate->es_evTupleNull[node->scanrelid - 1] = false;
+			return;
+		}
 		rel = scanstate->css_currentRelation;
 		scan = scanstate->css_currentScanDesc;
 		direction = estate->es_direction;

src/backend/nodes/copyfuncs.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/nodes/copyfuncs.c,v 1.55 1999/01/25 18:02:14 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/nodes/copyfuncs.c,v 1.56 1999/01/29 09:22:59 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -83,7 +83,6 @@ CopyPlanFields(Plan *from, Plan *newnode)
 	newnode->plan_size = from->plan_size;
 	newnode->plan_width = from->plan_width;
 	newnode->plan_tupperpage = from->plan_tupperpage;
-	newnode->state = from->state;
 	newnode->targetlist = copyObject(from->targetlist);
 	newnode->qual = copyObject(from->qual);
 	newnode->lefttree = copyObject(from->lefttree);
@@ -138,7 +137,6 @@ _copyResult(Result *from)
 	 * ----------------
 	 */
 	Node_Copy(from, newnode, resconstantqual);
-	Node_Copy(from, newnode, resstate);
 
 	return newnode;
 }
@@ -166,7 +164,6 @@ _copyAppend(Append *from)
 	Node_Copy(from, newnode, unionrtables);
 	newnode->inheritrelid = from->inheritrelid;
 	Node_Copy(from, newnode, inheritrtable);
-	Node_Copy(from, newnode, appendstate);
 
 	return newnode;
 }
@@ -183,7 +180,6 @@ static void
 CopyScanFields(Scan *from, Scan *newnode)
 {
 	newnode->scanrelid = from->scanrelid;
-	Node_Copy(from, newnode, scanstate);
 	return;
 }
 
@@ -248,7 +244,6 @@ _copyIndexScan(IndexScan *from)
 	newnode->indxid = listCopy(from->indxid);
 	Node_Copy(from, newnode, indxqual);
 	Node_Copy(from, newnode, indxqualorig);
-	Node_Copy(from, newnode, indxstate);
 
 	return newnode;
 }
@@ -304,12 +299,6 @@ _copyNestLoop(NestLoop *from)
 	CopyPlanFields((Plan *) from, (Plan *) newnode);
 	CopyJoinFields((Join *) from, (Join *) newnode);
 
-	/* ----------------
-	 *	copy remainder of node
-	 * ----------------
-	 */
-	Node_Copy(from, newnode, nlstate);
-
 	return newnode;
 }
 
@@ -346,8 +335,6 @@ _copyMergeJoin(MergeJoin *from)
 	newnode->mergeleftorder[0] = from->mergeleftorder[0];
 	newnode->mergeleftorder[1] = 0;
 
-	Node_Copy(from, newnode, mergestate);
-
 	return newnode;
 }
 
@@ -375,12 +362,9 @@ _copyHashJoin(HashJoin *from)
 
 	newnode->hashjoinop = from->hashjoinop;
 
-	Node_Copy(from, newnode, hashjoinstate);
-
-	newnode->hashjointable = from->hashjointable;
+	/* both are unused !.. */
 	newnode->hashjointablekey = from->hashjointablekey;
 	newnode->hashjointablesize = from->hashjointablesize;
-	newnode->hashdone = from->hashdone;
 
 	return newnode;
 }
@@ -437,12 +421,6 @@ _copyMaterial(Material *from)
 	CopyPlanFields((Plan *) from, (Plan *) newnode);
 	CopyTempFields((Temp *) from, (Temp *) newnode);
 
-	/* ----------------
-	 *	copy remainder of node
-	 * ----------------
-	 */
-	Node_Copy(from, newnode, matstate);
-
 	return newnode;
 }
 
@@ -463,14 +441,6 @@ _copySort(Sort *from)
 	CopyPlanFields((Plan *) from, (Plan *) newnode);
 	CopyTempFields((Temp *) from, (Temp *) newnode);
 
-	/* ----------------
-	 *	copy remainder of node
-	 * ----------------
-	 */
-	Node_Copy(from, newnode, sortstate);
-	Node_Copy(from, newnode, psortstate);
-	newnode->cleaned = from->cleaned;
-
 	return newnode;
 }
 
@@ -490,7 +460,6 @@ _copyGroup(Group *from)
 	newnode->numCols = from->numCols;
 	newnode->grpColIdx = palloc(from->numCols * sizeof(AttrNumber));
 	memcpy(newnode->grpColIdx, from->grpColIdx, from->numCols * sizeof(AttrNumber));
-	Node_Copy(from, newnode, grpstate);
 
 	return newnode;
 }
@@ -507,7 +476,6 @@ _copyAgg(Agg *from)
 	CopyPlanFields((Plan *) from, (Plan *) newnode);
 
 	newnode->aggs = get_agg_tlist_references(newnode);
-	Node_Copy(from, newnode, aggstate);
 
 	return newnode;
 }
@@ -553,7 +521,6 @@ _copyUnique(Unique *from)
 	else
 		newnode->uniqueAttr = NULL;
 	newnode->uniqueAttrNum = from->uniqueAttrNum;
-	Node_Copy(from, newnode, uniquestate);
 
 	return newnode;
 }
@@ -579,9 +546,8 @@ _copyHash(Hash *from)
 	 * ----------------
 	 */
 	Node_Copy(from, newnode, hashkey);
-	Node_Copy(from, newnode, hashstate);
 
-	newnode->hashtable = from->hashtable;
+	/* both are unused !.. */
 	newnode->hashtablekey = from->hashtablekey;
 	newnode->hashtablesize = from->hashtablesize;
 
@@ -599,7 +565,6 @@ _copySubPlan(SubPlan *from)
 	newnode->setParam = listCopy(from->setParam);
 	newnode->parParam = listCopy(from->parParam);
 	Node_Copy(from, newnode, sublink);
-	newnode->shutdown = from->shutdown;
 
 	return newnode;
 }
@@ -1901,7 +1866,7 @@ copyObject(void *from)
 			}
 			break;
 		default:
-			elog(NOTICE, "copyObject: don't know how to copy %d", nodeTag(from));
+			elog(ERROR, "copyObject: don't know how to copy %d", nodeTag(from));
 			retval = from;
 			break;
 	}

src/backend/parser/gram.c

@@ -239,7 +239,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/Attic/gram.c,v 2.64 1999/01/26 23:32:04 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/Attic/gram.c,v 2.65 1999/01/29 09:23:02 vadim Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -4791,7 +4791,7 @@ static const short yycheck[] = {     3,
     -1,    -1,    -1,    -1,    -1,    -1,    -1,   214
 };
 /* -*-C-*-  Note some compilers choke on comments on `#line' lines.  */
-#line 3 "/usr/local/bison/bison.simple"
+#line 3 "/usr/share/misc/bison.simple"
 
 /* Skeleton output parser for bison,
    Copyright (C) 1984, 1989, 1990 Free Software Foundation, Inc.
@@ -4984,7 +4984,7 @@ __yy_memcpy (char *to, char *from, int count)
 #endif
 #endif
 
-#line 196 "/usr/local/bison/bison.simple"
+#line 196 "/usr/share/misc/bison.simple"
 
 /* The user can define YYPARSE_PARAM as the name of an argument to be passed
    into yyparse.  The argument should have type void *.
@@ -11088,7 +11088,7 @@ case 960:
     break;}
 }
    /* the action file gets copied in in place of this dollarsign */
-#line 498 "/usr/local/bison/bison.simple"
+#line 498 "/usr/share/misc/bison.simple"
 
   yyvsp -= yylen;
   yyssp -= yylen;

src/backend/utils/time/tqual.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/time/tqual.c,v 1.23 1998/12/18 09:10:39 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/time/tqual.c,v 1.24 1999/01/29 09:23:12 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -368,6 +368,7 @@ bool
 HeapTupleSatisfiesDirty(HeapTupleHeader tuple)
 {
 	SnapshotDirty->xmin = SnapshotDirty->xmax = InvalidTransactionId;
+	ItemPointerSetInvalid(&(SnapshotDirty->tid));
 
 	if (AMI_OVERRIDE)
 		return true;
@@ -413,6 +414,7 @@ HeapTupleSatisfiesDirty(HeapTupleHeader tuple)
 	{
 		if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
 			return true;
+		SnapshotDirty->tid = tuple->t_ctid;
 		return false;							/* updated by other */
 	}
 
@@ -437,6 +439,7 @@ HeapTupleSatisfiesDirty(HeapTupleHeader tuple)
 	if (tuple->t_infomask & HEAP_MARKED_FOR_UPDATE)
 		return true;
 
+	SnapshotDirty->tid = tuple->t_ctid;
 	return false;								/* updated by other */
 }
 

src/include/nodes/execnodes.h

@@ -6,7 +6,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: execnodes.h,v 1.21 1999/01/25 12:01:19 vadim Exp $
+ * $Id: execnodes.h,v 1.22 1999/01/29 09:23:13 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -194,21 +194,27 @@ typedef struct JunkFilter
  */
 typedef struct EState
 {
-	NodeTag		type;
-	ScanDirection es_direction;
-	Snapshot	es_snapshot;
-	List	   *es_range_table;
-	RelationInfo *es_result_relation_info;
-	Relation	es_into_relation_descriptor;
-	ParamListInfo es_param_list_info;
-	ParamExecData *es_param_exec_vals;	/* this is for subselects */
-	int			es_BaseId;
-	TupleTable	es_tupleTable;
-	JunkFilter *es_junkFilter;
-	int		   *es_refcount;
-	uint32		es_processed;	/* # of tuples processed */
-	Oid			es_lastoid;		/* last oid processed (by INSERT) */
-	List	   *es_rowMark;		/* not good place, but there is no other */
+	NodeTag			type;
+	ScanDirection	es_direction;
+	Snapshot		es_snapshot;
+	List		   *es_range_table;
+	RelationInfo   *es_result_relation_info;
+	Relation		es_into_relation_descriptor;
+	ParamListInfo	es_param_list_info;
+	ParamExecData  *es_param_exec_vals;	/* this is for subselects */
+	int				es_BaseId;
+	TupleTable		es_tupleTable;
+	JunkFilter	   *es_junkFilter;
+	int			   *es_refcount;
+	uint32			es_processed;	/* # of tuples processed */
+	Oid				es_lastoid;		/* last oid processed (by INSERT) */
+	List		   *es_rowMark;		/* not good place, but there is no other */
+	/* Below is to re-evaluate plan qual in READ COMMITTED mode */
+	struct Plan	   *es_origPlan;
+	Pointer			es_evalPlanQual;
+	bool		   *es_evTupleNull;
+	HeapTuple	   *es_evTuple;
+	bool			es_useEvalPlan;
 } EState;
 
 /* ----------------

src/include/utils/tqual.h

@@ -7,7 +7,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: tqual.h,v 1.18 1998/12/18 09:09:55 vadim Exp $
+ * $Id: tqual.h,v 1.19 1999/01/29 09:23:17 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -22,6 +22,7 @@ typedef struct SnapshotData
 	TransactionId	xmax;			/* XID >= xmax are invisible to me */
 	uint32			xcnt;			/* # of xact below */
 	TransactionId  *xip;			/* array of xacts in progress */
+	ItemPointerData	tid;			/* required for Dirty snapshot -:( */
 }			SnapshotData;
 
 typedef SnapshotData *Snapshot;