Make DROP TABLE rollback-able: postpone physical file delete until commit.

(WAL logging for this is not done yet, however.)  Clean up a number of really
crufty things that are no longer needed now that DROP behaves nicely.  Make
temp table mapper do the right things when drop or rename affecting a temp
table is rolled back.  Also, remove "relation modified while in use" error
check, in favor of locking tables at first reference and holding that lock
throughout the statement.

9 files changed, 80 insertions, 71 deletions

diff --git a/src/backend/access/common/tupdesc.c b/src/backend/access/common/tupdesc.c
index 9b59947a882..1ed2366efda 100644
--- a/src/backend/access/common/tupdesc.c
+++ b/src/backend/access/common/tupdesc.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/common/tupdesc.c,v 1.67 2000/10/05 19:48:20 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/common/tupdesc.c,v 1.68 2000/11/08 22:09:53 tgl Exp $
  *
  * NOTES
  *	  some of the executor utility code such as "ExecTypeFromTL" should be
@@ -228,7 +228,9 @@ FreeTupleDesc(TupleDesc tupdesc)
 bool
 equalTupleDescs(TupleDesc tupdesc1, TupleDesc tupdesc2)
 {
-	int			i;
+	int			i,
+				j,
+				n;
 
 	if (tupdesc1->natts != tupdesc2->natts)
 		return false;
@@ -240,7 +242,9 @@ equalTupleDescs(TupleDesc tupdesc1, TupleDesc tupdesc2)
 		/*
 		 * We do not need to check every single field here, and in fact
 		 * some fields such as attdispersion probably shouldn't be
-		 * compared.
+		 * compared.  We can also disregard attnum (it was used to
+		 * place the row in the attrs array) and everything derived
+		 * from the column datatype.
 		 */
 		if (strcmp(NameStr(attr1->attname), NameStr(attr2->attname)) != 0)
 			return false;
@@ -260,32 +264,53 @@ equalTupleDescs(TupleDesc tupdesc1, TupleDesc tupdesc2)
 
 		if (constr2 == NULL)
 			return false;
-		if (constr1->num_defval != constr2->num_defval)
+		if (constr1->has_not_null != constr2->has_not_null)
+			return false;
+		n = constr1->num_defval;
+		if (n != (int) constr2->num_defval)
 			return false;
-		for (i = 0; i < (int) constr1->num_defval; i++)
+		for (i = 0; i < n; i++)
 		{
 			AttrDefault *defval1 = constr1->defval + i;
-			AttrDefault *defval2 = constr2->defval + i;
+			AttrDefault *defval2 = constr2->defval;
 
-			if (defval1->adnum != defval2->adnum)
+			/*
+			 * We can't assume that the items are always read from the
+			 * system catalogs in the same order; so use the adnum field to
+			 * identify the matching item to compare.
+			 */
+			for (j = 0; j < n; defval2++, j++)
+			{
+				if (defval1->adnum == defval2->adnum)
+					break;
+			}
+			if (j >= n)
 				return false;
 			if (strcmp(defval1->adbin, defval2->adbin) != 0)
 				return false;
 		}
-		if (constr1->num_check != constr2->num_check)
+		n = constr1->num_check;
+		if (n != (int) constr2->num_check)
 			return false;
-		for (i = 0; i < (int) constr1->num_check; i++)
+		for (i = 0; i < n; i++)
 		{
 			ConstrCheck *check1 = constr1->check + i;
-			ConstrCheck *check2 = constr2->check + i;
+			ConstrCheck *check2 = constr2->check;
 
-			if (strcmp(check1->ccname, check2->ccname) != 0)
-				return false;
-			if (strcmp(check1->ccbin, check2->ccbin) != 0)
+			/*
+			 * Similarly, don't assume that the checks are always read
+			 * in the same order; match them up by name and contents.
+			 * (The name *should* be unique, but...)
+			 */
+			for (j = 0; j < n; check2++, j++)
+			{
+				if (strcmp(check1->ccname, check2->ccname) == 0 &&
+					strcmp(check1->ccbin, check2->ccbin) == 0)
+					break;
+			}
+			if (j >= n)
 				return false;
 		}
-		if (constr1->has_not_null != constr2->has_not_null)
-			return false;
 	}
 	else if (tupdesc2->constr != NULL)
 		return false;
diff --git a/src/backend/access/gist/gist.c b/src/backend/access/gist/gist.c
index 560f28743f9..d7bfeb1287d 100644
--- a/src/backend/access/gist/gist.c
+++ b/src/backend/access/gist/gist.c
@@ -6,7 +6,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/gist/gist.c,v 1.63 2000/10/21 15:43:09 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/gist/gist.c,v 1.64 2000/11/08 22:09:53 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -266,13 +266,12 @@ gistbuild(PG_FUNCTION_ARGS)
 	{
 		Oid			hrelid = RelationGetRelid(heap);
 		Oid			irelid = RelationGetRelid(index);
-		bool		inplace = IsReindexProcessing();
 
 		heap_close(heap, NoLock);
 		index_close(index);
-		UpdateStats(hrelid, nhtups, inplace);
-		UpdateStats(irelid, nitups, inplace);
-		if (oldPred != NULL && !inplace)
+		UpdateStats(hrelid, nhtups);
+		UpdateStats(irelid, nitups);
+		if (oldPred != NULL)
 		{
 			if (nitups == nhtups)
 				pred = NULL;
diff --git a/src/backend/access/hash/hash.c b/src/backend/access/hash/hash.c
index 8db80d5154f..333199a898e 100644
--- a/src/backend/access/hash/hash.c
+++ b/src/backend/access/hash/hash.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/hash/hash.c,v 1.43 2000/10/21 15:43:11 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/hash/hash.c,v 1.44 2000/11/08 22:09:54 tgl Exp $
  *
  * NOTES
  *	  This file contains only the public interface routines.
@@ -217,13 +217,12 @@ hashbuild(PG_FUNCTION_ARGS)
 	{
 		Oid			hrelid = RelationGetRelid(heap);
 		Oid			irelid = RelationGetRelid(index);
-		bool		inplace = IsReindexProcessing();
 
 		heap_close(heap, NoLock);
 		index_close(index);
-		UpdateStats(hrelid, nhtups, inplace);
-		UpdateStats(irelid, nitups, inplace);
-		if (oldPred != NULL && !inplace)
+		UpdateStats(hrelid, nhtups);
+		UpdateStats(irelid, nitups);
+		if (oldPred != NULL)
 		{
 			if (nitups == nhtups)
 				pred = NULL;
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index e796762ef16..5f450f91524 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.92 2000/10/29 18:33:39 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.93 2000/11/08 22:09:54 tgl Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -780,19 +780,13 @@ heap_beginscan(Relation relation,
 
 	/* ----------------
 	 *	increment relation ref count while scanning relation
-	 * ----------------
-	 */
-	RelationIncrementReferenceCount(relation);
-
-	/* ----------------
-	 *	Acquire AccessShareLock for the duration of the scan
 	 *
-	 *	Note: we could get an SI inval message here and consequently have
-	 *	to rebuild the relcache entry.	The refcount increment above
-	 *	ensures that we will rebuild it and not just flush it...
+	 *	This is just to make really sure the relcache entry won't go away
+	 *	while the scan has a pointer to it.  Caller should be holding the
+	 *	rel open anyway, so this is redundant in all normal scenarios...
 	 * ----------------
 	 */
-	LockRelation(relation, AccessShareLock);
+	RelationIncrementReferenceCount(relation);
 
 	/* XXX someday assert SelfTimeQual if relkind == RELKIND_UNCATALOGED */
 	if (relation->rd_rel->relkind == RELKIND_UNCATALOGED)
@@ -809,13 +803,11 @@ heap_beginscan(Relation relation,
 	scan->rs_snapshot = snapshot;
 	scan->rs_nkeys = (short) nkeys;
 
+	/*
+	 * we do this here instead of in initscan() because heap_rescan
+	 * also calls initscan() and we don't want to allocate memory again
+	 */
 	if (nkeys)
-
-		/*
-		 * we do this here instead of in initscan() because heap_rescan
-		 * also calls initscan() and we don't want to allocate memory
-		 * again
-		 */
 		scan->rs_key = (ScanKey) palloc(sizeof(ScanKeyData) * nkeys);
 	else
 		scan->rs_key = NULL;
@@ -841,8 +833,6 @@ heap_rescan(HeapScanDesc scan,
 	IncrHeapAccessStat(local_rescan);
 	IncrHeapAccessStat(global_rescan);
 
-	/* Note: set relation level read lock is still set */
-
 	/* ----------------
 	 *	unpin scan buffers
 	 * ----------------
@@ -853,7 +843,7 @@ heap_rescan(HeapScanDesc scan,
 	 *	reinitialize scan descriptor
 	 * ----------------
 	 */
-	scan->rs_atend = (bool) scanFromEnd;
+	scan->rs_atend = scanFromEnd;
 	initscan(scan, scan->rs_rd, scanFromEnd, scan->rs_nkeys, key);
 }
 
@@ -883,12 +873,6 @@ heap_endscan(HeapScanDesc scan)
 	unpinscan(scan);
 
 	/* ----------------
-	 *	Release AccessShareLock acquired by heap_beginscan()
-	 * ----------------
-	 */
-	UnlockRelation(scan->rs_rd, AccessShareLock);
-
-	/* ----------------
 	 *	decrement relation reference count and free scan descriptor storage
 	 * ----------------
 	 */
diff --git a/src/backend/access/nbtree/nbtree.c b/src/backend/access/nbtree/nbtree.c
index fb437ac99f4..ab942844afd 100644
--- a/src/backend/access/nbtree/nbtree.c
+++ b/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 1.69 2000/11/01 20:39:58 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtree.c,v 1.70 2000/11/08 22:09:55 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -340,19 +340,16 @@ btbuild(PG_FUNCTION_ARGS)
 	{
 		Oid			hrelid = RelationGetRelid(heap);
 		Oid			irelid = RelationGetRelid(index);
-		bool		inplace = IsReindexProcessing();
 
 		heap_close(heap, NoLock);
 		index_close(index);
-
-		UpdateStats(hrelid, nhtups, inplace);
-		UpdateStats(irelid, nitups, inplace);
+		UpdateStats(hrelid, nhtups);
+		UpdateStats(irelid, nitups);
 		if (oldPred != NULL)
 		{
 			if (nitups == nhtups)
 				pred = NULL;
-			if (!inplace)
-				UpdateIndexPredicate(irelid, oldPred, pred);
+			UpdateIndexPredicate(irelid, oldPred, pred);
 		}
 	}
 
diff --git a/src/backend/access/rtree/rtree.c b/src/backend/access/rtree/rtree.c
index 60f6a2f6ca9..ee5f621c0c3 100644
--- a/src/backend/access/rtree/rtree.c
+++ b/src/backend/access/rtree/rtree.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/rtree/Attic/rtree.c,v 1.54 2000/10/21 15:43:20 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/rtree/Attic/rtree.c,v 1.55 2000/11/08 22:09:55 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -237,13 +237,12 @@ rtbuild(PG_FUNCTION_ARGS)
 	{
 		Oid			hrelid = RelationGetRelid(heap);
 		Oid			irelid = RelationGetRelid(index);
-		bool		inplace = IsReindexProcessing();
 
 		heap_close(heap, NoLock);
 		index_close(index);
-		UpdateStats(hrelid, nhtups, inplace);
-		UpdateStats(irelid, nitups, inplace);
-		if (oldPred != NULL && !inplace)
+		UpdateStats(hrelid, nhtups);
+		UpdateStats(irelid, nitups);
+		if (oldPred != NULL)
 		{
 			if (nitups == nhtups)
 				pred = NULL;
diff --git a/src/backend/access/transam/varsup.c b/src/backend/access/transam/varsup.c
index f29b41d749c..8c7d98ca707 100644
--- a/src/backend/access/transam/varsup.c
+++ b/src/backend/access/transam/varsup.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/transam/varsup.c,v 1.31 2000/11/03 11:39:35 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/transam/varsup.c,v 1.32 2000/11/08 22:09:55 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -130,7 +130,7 @@ VariableRelationPutNextXid(TransactionId xid)
 
 	TransactionIdStore(xid, &(var->nextXidData));
 
-	FlushBuffer(buf, TRUE);
+	FlushBuffer(buf, true, true);
 }
 
 /* --------------------------------
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index cc4209fa51f..97ff91fc440 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/transam/xact.c,v 1.80 2000/11/05 22:50:19 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/transam/xact.c,v 1.81 2000/11/08 22:09:55 tgl Exp $
  *
  * NOTES
  *		Transaction aborts can now occur two ways:
@@ -167,6 +167,7 @@
 #include "miscadmin.h"
 #include "storage/proc.h"
 #include "storage/sinval.h"
+#include "storage/smgr.h"
 #include "utils/inval.h"
 #include "utils/memutils.h"
 #include "utils/portal.h"
@@ -1105,6 +1106,9 @@ CommitTransaction(void)
 	}
 
 	RelationPurgeLocalRelation(true);
+	AtEOXact_temp_relations(true);
+	smgrDoPendingDeletes(true);
+
 	AtEOXact_SPI();
 	AtEOXact_nbtree();
 	AtCommit_Cache();
@@ -1181,8 +1185,11 @@ AbortTransaction(void)
 	CloseSequences();
 	AtEOXact_portals();
 	RecordTransactionAbort();
+
 	RelationPurgeLocalRelation(false);
-	remove_temp_rel_in_myxid();
+	AtEOXact_temp_relations(false);
+	smgrDoPendingDeletes(false);
+
 	AtEOXact_SPI();
 	AtEOXact_nbtree();
 	AtAbort_Cache();
diff --git a/src/backend/access/transam/xlogutils.c b/src/backend/access/transam/xlogutils.c
index 1fdc7e83fb5..b6442787334 100644
--- a/src/backend/access/transam/xlogutils.c
+++ b/src/backend/access/transam/xlogutils.c
@@ -171,9 +171,8 @@ XLogOpenLogRelation(void)
 	sprintf(RelationGetPhysicalRelationName(logRelation), "pg_log");
 	logRelation->rd_node.tblNode = InvalidOid;
 	logRelation->rd_node.relNode = RelOid_pg_log;
-	logRelation->rd_unlinked = false;	/* must exists */
 	logRelation->rd_fd = -1;
-	logRelation->rd_fd = smgropen(DEFAULT_SMGR, logRelation);
+	logRelation->rd_fd = smgropen(DEFAULT_SMGR, logRelation, false);
 	if (logRelation->rd_fd < 0)
 		elog(STOP, "XLogOpenLogRelation: failed to open pg_log");
 	LogRelation = logRelation;
@@ -384,9 +383,9 @@ XLogOpenRelation(bool redo, RmgrId rmid, RelFileNode rnode)
 
 		hentry->rdesc = res;
 
-		res->reldata.rd_unlinked = true;	/* look smgropen */
 		res->reldata.rd_fd = -1;
-		res->reldata.rd_fd = smgropen(DEFAULT_SMGR, &(res->reldata));
+		res->reldata.rd_fd = smgropen(DEFAULT_SMGR, &(res->reldata),
+									  true /* allow failure */);
 	}
 
 	res->moreRecently = &(_xlrelarr[0]);