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Remove heap_mark4update from AlterTableCreateToastTable. This has 

never been the correct procedure for locking a relation, and the
recently-found ALTER TABLE bug with adding a constraint and a toast
table in the same command shows why it's a bad idea.
This commit is contained in:
Tom Lane 2002-09-06 00:01:53 +00:00
parent 6fe27ca2fb
commit 9a9825f96a
1 changed files with 15 additions and 37 deletions
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52
src/backend/commands/tablecmds.c
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@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/commands/tablecmds.c,v 1.39 2002/09/04 20:31:15 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/commands/tablecmds.c,v 1.40 2002/09/06 00:01:53 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -3325,11 +3325,9 @@ AlterTableCreateToastTable(Oid relOid, bool silent)
{
Relation rel;
HeapTuple reltup;
HeapTupleData classtuple;
TupleDesc tupdesc;
bool shared_relation;
Relation class_rel;
Buffer buffer;
Oid toast_relid;
Oid toast_idxid;
char toast_relname[NAMEDATALEN];
@ -3366,42 +3364,14 @@ AlterTableCreateToastTable(Oid relOid, bool silent)
if (shared_relation && IsUnderPostmaster)
elog(ERROR, "Shared relations cannot be toasted after initdb");
/*
* lock the pg_class tuple for update (is that really needed?)
*/
class_rel = heap_openr(RelationRelationName, RowExclusiveLock);
reltup = SearchSysCache(RELOID,
ObjectIdGetDatum(relOid),
0, 0, 0);
if (!HeapTupleIsValid(reltup))
elog(ERROR, "ALTER TABLE: relation \"%s\" not found",
RelationGetRelationName(rel));
classtuple.t_self = reltup->t_self;
ReleaseSysCache(reltup);
switch (heap_mark4update(class_rel, &classtuple, &buffer,
GetCurrentCommandId()))
{
case HeapTupleSelfUpdated:
case HeapTupleMayBeUpdated:
break;
default:
elog(ERROR, "couldn't lock pg_class tuple");
}
reltup = heap_copytuple(&classtuple);
ReleaseBuffer(buffer);
/*
* Is it already toasted?
*/
if (((Form_pg_class) GETSTRUCT(reltup))->reltoastrelid != InvalidOid)
if (rel->rd_rel->reltoastrelid != InvalidOid)
{
if (silent)
{
heap_close(rel, NoLock);
heap_close(class_rel, NoLock);
heap_freetuple(reltup);
return;
}
@ -3417,8 +3387,6 @@ AlterTableCreateToastTable(Oid relOid, bool silent)
if (silent)
{
heap_close(rel, NoLock);
heap_close(class_rel, NoLock);
heap_freetuple(reltup);
return;
}
@ -3509,8 +3477,17 @@ AlterTableCreateToastTable(Oid relOid, bool silent)
setRelhasindex(toast_relid, true, true, toast_idxid);
/*
* Store the toast table's OID in the parent relation's tuple
* Store the toast table's OID in the parent relation's pg_class row
*/
class_rel = heap_openr(RelationRelationName, RowExclusiveLock);
reltup = SearchSysCacheCopy(RELOID,
ObjectIdGetDatum(relOid),
0, 0, 0);
if (!HeapTupleIsValid(reltup))
elog(ERROR, "ALTER TABLE: relation \"%s\" not found",
RelationGetRelationName(rel));
((Form_pg_class) GETSTRUCT(reltup))->reltoastrelid = toast_relid;
simple_heap_update(class_rel, &reltup->t_self, reltup);
@ -3520,6 +3497,8 @@ AlterTableCreateToastTable(Oid relOid, bool silent)
heap_freetuple(reltup);
heap_close(class_rel, RowExclusiveLock);
/*
* Register dependency from the toast table to the master, so that the
* toast table will be deleted if the master is.
@ -3534,9 +3513,8 @@ AlterTableCreateToastTable(Oid relOid, bool silent)
recordDependencyOn(&toastobject, &baseobject, DEPENDENCY_INTERNAL);
/*
* Close relations and make changes visible
* Clean up and make changes visible
*/
heap_close(class_rel, NoLock);
heap_close(rel, NoLock);
CommandCounterIncrement();