CREATE btree INDEX takes dead tuples into account when old transactions

are running.

src/backend/access/nbtree/nbtree.c

@@ -12,7 +12,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtree.c,v 1.62 2000/07/21 06:42:32 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtree.c,v 1.63 2000/08/10 02:33:20 inoue Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -25,6 +25,7 @@
 #include "catalog/index.h"
 #include "executor/executor.h"
 #include "miscadmin.h"
+#include "storage/sinval.h"
 
 
 bool		BuildingBtree = false;		/* see comment in btbuild() */
@@ -70,6 +71,16 @@ btbuild(PG_FUNCTION_ARGS)
 	BTSpool    *spool = NULL;
 	BTItem		btitem;
 	bool		usefast;
+	Snapshot	snapshot;
+	TransactionId	XmaxRecent;
+	/*
+	 * spool2 is needed only when the index is an unique index.
+	 * Dead tuples are put into spool2 instead of spool in
+	 * order to avoid uniqueness check.
+	 */
+	BTSpool		*spool2 = NULL;
+	bool		tupleIsAlive;
+	int		dead_count;
 
 	/* note that this is a new btree */
 	BuildingBtree = true;
@@ -135,13 +146,41 @@ btbuild(PG_FUNCTION_ARGS)
 	nhtups = nitups = 0;
 
 	if (usefast)
+	{
 		spool = _bt_spoolinit(index, indexInfo->ii_Unique);
+		/*
+	 	 * Different from spool,the uniqueness isn't checked
+		 * for spool2.
+	 	 */
+		if (indexInfo->ii_Unique)
+			spool2 = _bt_spoolinit(index, false);
+	}
 
 	/* start a heap scan */
-	hscan = heap_beginscan(heap, 0, SnapshotNow, 0, (ScanKey) NULL);
+	dead_count = 0;
+	snapshot = (IsBootstrapProcessingMode() ? SnapshotNow : SnapshotAny);
+	hscan = heap_beginscan(heap, 0, snapshot, 0, (ScanKey) NULL);
+	XmaxRecent = 0;
+	if (snapshot == SnapshotAny)
+		GetXmaxRecent(&XmaxRecent);
 
 	while (HeapTupleIsValid(htup = heap_getnext(hscan, 0)))
 	{
+		if (snapshot == SnapshotAny)
+		{
+			tupleIsAlive = HeapTupleSatisfiesNow(htup->t_data);
+			if (!tupleIsAlive)
+			{
+				if ((htup->t_data->t_infomask & HEAP_XMIN_INVALID) != 0)
+					continue;
+				if (htup->t_data->t_infomask & HEAP_XMAX_COMMITTED &&
+					htup->t_data->t_xmax < XmaxRecent)
+					continue;
+			}
+		}
+		else
+			tupleIsAlive = true;
+		
 		MemoryContextReset(econtext->ecxt_per_tuple_memory);
 
 		nhtups++;
@@ -222,7 +261,15 @@ btbuild(PG_FUNCTION_ARGS)
 		 * into the btree.
 		 */
 		if (usefast)
+		{
+			if (tupleIsAlive || !spool2)
 				_bt_spool(btitem, spool);
+			else /* dead tuples are put into spool2 */
+			{
+				dead_count++;
+				_bt_spool(btitem, spool2);
+			}
+		}
 		else
 			res = _bt_doinsert(index, btitem, indexInfo->ii_Unique, heap);
 
@@ -234,6 +281,11 @@ btbuild(PG_FUNCTION_ARGS)
 
 	/* okay, all heap tuples are indexed */
 	heap_endscan(hscan);
+	if (spool2 && !dead_count) /* spool2 was found to be unnecessary */
+	{
+		_bt_spooldestroy(spool2);
+		spool2 = NULL;
+	}
 
 #ifndef OMIT_PARTIAL_INDEX
 	if (pred != NULL || oldPred != NULL)
@@ -250,8 +302,10 @@ btbuild(PG_FUNCTION_ARGS)
 	 */
 	if (usefast)
 	{
-		_bt_leafbuild(spool);
+		_bt_leafbuild(spool, spool2);
 		_bt_spooldestroy(spool);
+		if (spool2)
+			_bt_spooldestroy(spool2);
 	}
 
 #ifdef BTREE_BUILD_STATS

src/backend/access/nbtree/nbtsort.c

@@ -35,7 +35,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtsort.c,v 1.56 2000/07/21 22:14:09 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtsort.c,v 1.57 2000/08/10 02:33:20 inoue Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -95,7 +95,7 @@ static void _bt_sortaddtup(Page page, Size itemsize,
 						   BTItem btitem, OffsetNumber itup_off);
 static void _bt_buildadd(Relation index, BTPageState *state, BTItem bti);
 static void _bt_uppershutdown(Relation index, BTPageState *state);
-static void _bt_load(Relation index, BTSpool *btspool);
+static void _bt_load(Relation index, BTSpool *btspool, BTSpool *btspool2);
 
 
 /*
@@ -153,7 +153,7 @@ _bt_spool(BTItem btitem, BTSpool *btspool)
  * create an entire btree.
  */
 void
-_bt_leafbuild(BTSpool *btspool)
+_bt_leafbuild(BTSpool *btspool, BTSpool *btspool2)
 {
 #ifdef BTREE_BUILD_STATS
 	if (Show_btree_build_stats)
@@ -165,7 +165,9 @@ _bt_leafbuild(BTSpool *btspool)
 #endif /* BTREE_BUILD_STATS */
 	tuplesort_performsort(btspool->sortstate);
 
-	_bt_load(btspool->index, btspool);
+	if (btspool2)
+		tuplesort_performsort(btspool2->sortstate);
+	_bt_load(btspool->index, btspool, btspool2);
 }
 
 
@@ -523,29 +525,107 @@ _bt_uppershutdown(Relation index, BTPageState *state)
  * btree leaves.
  */
 static void
-_bt_load(Relation index, BTSpool *btspool)
+_bt_load(Relation index, BTSpool *btspool, BTSpool *btspool2)
 {
 	BTPageState *state = NULL;
-
+	bool		merge = (btspool2 != NULL);
+	BTItem		bti, bti2 = NULL;
+	bool		should_free, should_free2, load1;
+	TupleDesc	tupdes = RelationGetDescr(index);
+	int		i, keysz = RelationGetNumberOfAttributes(index);
+	ScanKey		indexScanKey = NULL;
+
+	if (merge)
+	{
+		/*
+	 	 * Another BTSpool for dead tuples exists.
+	 	 * Now we have to merge btspool and btspool2.
+	 	 */
+		ScanKey	entry;
+		Datum	attrDatum1, attrDatum2;
+		bool	isFirstNull, isSecondNull;
+		int32	compare;
+
+		/* the preparation of merge */
+		bti = (BTItem) tuplesort_getindextuple(btspool->sortstate, true, &should_free);
+		bti2 = (BTItem) tuplesort_getindextuple(btspool2->sortstate, true, &should_free2);
+		indexScanKey = _bt_mkscankey_nodata(index);
 		for (;;)
 		{
-		BTItem		bti;
-		bool		should_free;
+			load1 = true; /* load BTSpool next ? */
+			if (NULL == bti2)
+			{
+				if (NULL == bti)
+					break;
+			}
+			else if (NULL != bti)
+			{
 
-		bti = (BTItem) tuplesort_getindextuple(btspool->sortstate, true,
-											   &should_free);
-		if (bti == (BTItem) NULL)
+				for (i = 1; i <= keysz; i++)
+				{
+					entry = indexScanKey + i - 1;
+					attrDatum1 = index_getattr((IndexTuple)bti, i, tupdes, &isFirstNull);
+					attrDatum2 = index_getattr((IndexTuple)bti2, i, tupdes, &isSecondNull);
+					if (isFirstNull)
+					{
+						if (!isSecondNull)
+						{
+							load1 = false;
+							break;
+						}
+					}
+					else if (isSecondNull)
+						break;
+					else
+					{
+						compare = DatumGetInt32(FunctionCall2(&entry->sk_func, attrDatum1, attrDatum2));
+						if (compare > 0)
+						{
+							load1 = false;
+							break;
+						}
+						else if (compare < 0)
 							break;
+					}	
+				}
+			}
+			else
+				load1 = false;
 
 			/* When we see first tuple, create first index page */
 			if (state == NULL)
 				state = _bt_pagestate(index, BTP_LEAF, 0);
 
+			if (load1)
+			{
 				_bt_buildadd(index, state, bti);
+				if (should_free)
+					pfree((void *) bti);
+				bti = (BTItem) tuplesort_getindextuple(btspool->sortstate, true, &should_free);
+			}
+			else
+			{
+				_bt_buildadd(index, state, bti2);
+				if (should_free2)
+					pfree((void *) bti2);
+				bti2 = (BTItem) tuplesort_getindextuple(btspool2->sortstate, true, &should_free2);
+			}
+		}
+		_bt_freeskey(indexScanKey);
+	}
+	else	/* merge is unnecessary */
+	{
+		while (bti = (BTItem) tuplesort_getindextuple(btspool->sortstate, true, &should_free), bti != (BTItem) NULL)
+		{
+			/* When we see first tuple, create first index page */
+			if (state == NULL)
+				state = _bt_pagestate(index, BTP_LEAF, 0);
 
+			_bt_buildadd(index, state, bti);
 			if (should_free)
 				pfree((void *) bti);
 		}
+	}
 
 	/* Close down final pages, if we had any data at all */
 	if (state != NULL)

src/include/access/nbtree.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: nbtree.h,v 1.40 2000/07/25 04:47:57 tgl Exp $
+ * $Id: nbtree.h,v 1.41 2000/08/10 02:33:19 inoue Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -289,6 +289,6 @@ typedef struct BTSpool BTSpool; /* opaque type known only within nbtsort.c */
 extern BTSpool *_bt_spoolinit(Relation index, bool isunique);
 extern void _bt_spooldestroy(BTSpool *btspool);
 extern void _bt_spool(BTItem btitem, BTSpool *btspool);
-extern void _bt_leafbuild(BTSpool *btspool);
+extern void _bt_leafbuild(BTSpool *btspool, BTSpool *spool2);
 
 #endif	 /* NBTREE_H */