— see <xref linkend="SQL-CREATEINDEX-CONCURRENTLY"
endterm="SQL-CREATEINDEX-CONCURRENTLY-title">.
</para>
+ <para>
+ For temporary tables, <command>CREATE INDEX</command> is always
+ non-concurrent, as no other session can access them, and
+ non-concurrent index creation is cheaper.
+ </para>
</listitem>
</varlistentry>
performed within a transaction block, but
<command>DROP INDEX CONCURRENTLY</> cannot.
</para>
+ <para>
+ For temporary tables, <command>DROP INDEX</command> is always
+ non-concurrent, as no other session can access them, and
+ non-concurrent index drop is cheaper.
+ </para>
</listitem>
</varlistentry>
LOCKTAG heaplocktag;
LOCKMODE lockmode;
+ /*
+ * A temporary relation uses a non-concurrent DROP. Other backends can't
+ * access a temporary relation, so there's no harm in grabbing a stronger
+ * lock (see comments in RemoveRelations), and a non-concurrent DROP is
+ * more efficient.
+ */
+ Assert(get_rel_persistence(indexId) != RELPERSISTENCE_TEMP ||
+ !concurrent);
+
/*
* To drop an index safely, we must grab exclusive lock on its parent
* table. Exclusive lock on the index alone is insufficient because
bool skip_build,
bool quiet)
{
+ bool concurrent;
char *indexRelationName;
char *accessMethodName;
Oid *typeObjectId;
Snapshot snapshot;
int i;
+ /*
+ * Force non-concurrent build on temporary relations, even if CONCURRENTLY
+ * was requested. Other backends can't access a temporary relation, so
+ * there's no harm in grabbing a stronger lock, and a non-concurrent DROP
+ * is more efficient. Do this before any use of the concurrent option is
+ * done.
+ */
+ if (stmt->concurrent && get_rel_persistence(relationId) != RELPERSISTENCE_TEMP)
+ concurrent = true;
+ else
+ concurrent = false;
+
/*
* count attributes in index
*/
* relation. To avoid lock upgrade hazards, that lock should be at least
* as strong as the one we take here.
*/
- lockmode = stmt->concurrent ? ShareUpdateExclusiveLock : ShareLock;
+ lockmode = concurrent ? ShareUpdateExclusiveLock : ShareLock;
rel = heap_open(relationId, lockmode);
relationId = RelationGetRelid(rel);
indexInfo->ii_ExclusionStrats = NULL;
indexInfo->ii_Unique = stmt->unique;
/* In a concurrent build, mark it not-ready-for-inserts */
- indexInfo->ii_ReadyForInserts = !stmt->concurrent;
- indexInfo->ii_Concurrent = stmt->concurrent;
+ indexInfo->ii_ReadyForInserts = !concurrent;
+ indexInfo->ii_Concurrent = concurrent;
indexInfo->ii_BrokenHotChain = false;
typeObjectId = (Oid *) palloc(numberOfAttributes * sizeof(Oid));
* A valid stmt->oldNode implies that we already have a built form of the
* index. The caller should also decline any index build.
*/
- Assert(!OidIsValid(stmt->oldNode) || (skip_build && !stmt->concurrent));
+ Assert(!OidIsValid(stmt->oldNode) || (skip_build && !concurrent));
/*
* Make the catalog entries for the index, including constraints. Then, if
coloptions, reloptions, stmt->primary,
stmt->isconstraint, stmt->deferrable, stmt->initdeferred,
allowSystemTableMods,
- skip_build || stmt->concurrent,
- stmt->concurrent, !check_rights);
+ skip_build || concurrent,
+ concurrent, !check_rights);
/* Add any requested comment */
if (stmt->idxcomment != NULL)
CreateComments(indexRelationId, RelationRelationId, 0,
stmt->idxcomment);
- if (!stmt->concurrent)
+ if (!concurrent)
{
/* Close the heap and we're done, in the non-concurrent case */
heap_close(rel, NoLock);
/* DROP CONCURRENTLY uses a weaker lock, and has some restrictions */
if (drop->concurrent)
{
- flags |= PERFORM_DELETION_CONCURRENTLY;
+ /*
+ * Note that for temporary relations this lock may get upgraded
+ * later on, but as no other session can access a temporary
+ * relation, this is actually fine.
+ */
lockmode = ShareUpdateExclusiveLock;
Assert(drop->removeType == OBJECT_INDEX);
if (list_length(drop->objects) != 1)
continue;
}
+ /*
+ * Decide if concurrent mode needs to be used here or not. The
+ * relation persistence cannot be known without its OID.
+ */
+ if (drop->concurrent &&
+ get_rel_persistence(relOid) != RELPERSISTENCE_TEMP)
+ {
+ Assert(list_length(drop->objects) == 1 &&
+ drop->removeType == OBJECT_INDEX);
+ flags |= PERFORM_DELETION_CONCURRENTLY;
+ }
+
/* OK, we're ready to delete this one */
obj.classId = RelationRelationId;
obj.objectId = relOid;
return InvalidOid;
}
+/*
+ * get_rel_persistence
+ *
+ * Returns the relpersistence associated with a given relation.
+ */
+char
+get_rel_persistence(Oid relid)
+{
+ HeapTuple tp;
+ Form_pg_class reltup;
+ char result;
+
+ tp = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
+ if (!HeapTupleIsValid(tp))
+ elog(ERROR, "cache lookup failed for relation %u", relid);
+ reltup = (Form_pg_class) GETSTRUCT(tp);
+ result = reltup->relpersistence;
+ ReleaseSysCache(tp);
+
+ return result;
+}
+
/* ---------- TYPE CACHE ---------- */
extern Oid get_rel_type_id(Oid relid);
extern char get_rel_relkind(Oid relid);
extern Oid get_rel_tablespace(Oid relid);
+extern char get_rel_persistence(Oid relid);
extern bool get_typisdefined(Oid typid);
extern int16 get_typlen(Oid typid);
extern bool get_typbyval(Oid typid);
"concur_index5" btree (f2) WHERE f1 = 'x'::text
"std_index" btree (f2)
+-- Temporary tables with concurrent builds and on-commit actions
+-- CONCURRENTLY used with CREATE INDEX and DROP INDEX is ignored.
+-- PRESERVE ROWS, the default.
+CREATE TEMP TABLE concur_temp (f1 int, f2 text)
+ ON COMMIT PRESERVE ROWS;
+INSERT INTO concur_temp VALUES (1, 'foo'), (2, 'bar');
+CREATE INDEX CONCURRENTLY concur_temp_ind ON concur_temp(f1);
+DROP INDEX CONCURRENTLY concur_temp_ind;
+DROP TABLE concur_temp;
+-- ON COMMIT DROP
+BEGIN;
+CREATE TEMP TABLE concur_temp (f1 int, f2 text)
+ ON COMMIT DROP;
+INSERT INTO concur_temp VALUES (1, 'foo'), (2, 'bar');
+-- Fails when running in a transaction.
+CREATE INDEX CONCURRENTLY concur_temp_ind ON concur_temp(f1);
+ERROR: CREATE INDEX CONCURRENTLY cannot run inside a transaction block
+COMMIT;
+-- ON COMMIT DELETE ROWS
+CREATE TEMP TABLE concur_temp (f1 int, f2 text)
+ ON COMMIT DELETE ROWS;
+INSERT INTO concur_temp VALUES (1, 'foo'), (2, 'bar');
+CREATE INDEX CONCURRENTLY concur_temp_ind ON concur_temp(f1);
+DROP INDEX CONCURRENTLY concur_temp_ind;
+DROP TABLE concur_temp;
--
-- Try some concurrent index drops
--
REINDEX TABLE concur_heap;
\d concur_heap
+-- Temporary tables with concurrent builds and on-commit actions
+-- CONCURRENTLY used with CREATE INDEX and DROP INDEX is ignored.
+-- PRESERVE ROWS, the default.
+CREATE TEMP TABLE concur_temp (f1 int, f2 text)
+ ON COMMIT PRESERVE ROWS;
+INSERT INTO concur_temp VALUES (1, 'foo'), (2, 'bar');
+CREATE INDEX CONCURRENTLY concur_temp_ind ON concur_temp(f1);
+DROP INDEX CONCURRENTLY concur_temp_ind;
+DROP TABLE concur_temp;
+-- ON COMMIT DROP
+BEGIN;
+CREATE TEMP TABLE concur_temp (f1 int, f2 text)
+ ON COMMIT DROP;
+INSERT INTO concur_temp VALUES (1, 'foo'), (2, 'bar');
+-- Fails when running in a transaction.
+CREATE INDEX CONCURRENTLY concur_temp_ind ON concur_temp(f1);
+COMMIT;
+-- ON COMMIT DELETE ROWS
+CREATE TEMP TABLE concur_temp (f1 int, f2 text)
+ ON COMMIT DELETE ROWS;
+INSERT INTO concur_temp VALUES (1, 'foo'), (2, 'bar');
+CREATE INDEX CONCURRENTLY concur_temp_ind ON concur_temp(f1);
+DROP INDEX CONCURRENTLY concur_temp_ind;
+DROP TABLE concur_temp;
+
--
-- Try some concurrent index drops
--
projects / postgresql.git / commitdiff