database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-08-15 14:02:29 +03:00
Code Activity

Reduce lock levels of some ALTER TABLE cmds

Browse Source 
VALIDATE CONSTRAINT

CLUSTER ON
SET WITHOUT CLUSTER

ALTER COLUMN SET STATISTICS
ALTER COLUMN SET ()
ALTER COLUMN RESET ()

All other sub-commands use AccessExclusiveLock

Simon Riggs and Noah Misch

Reviews by Robert Haas and Andres Freund
This commit is contained in:
Simon Riggs
2014-04-06 11:13:43 -04:00
parent 80a5cf643a
commit e5550d5fec
13 changed files with 402 additions and 120 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
src/backend/commands/cluster.c
View File

@@ -408,10 +408,10 @@ cluster_rel(Oid tableOid, Oid indexOid, bool recheck, bool verbose)
/*
* Verify that the specified heap and index are valid to cluster on
*
* Side effect: obtains exclusive lock on the index. The caller should
* already have exclusive lock on the table, so the index lock is likely
* redundant, but it seems best to grab it anyway to ensure the index
* definition can't change under us.
* Side effect: obtains lock on the index. The caller may
* in some cases already have AccessExclusiveLock on the table, but
* not in all cases so we can't rely on the table-level lock for
* protection here.
*/
void
check_index_is_clusterable(Relation OldHeap, Oid indexOid, bool recheck, LOCKMODE lockmode)
@@ -696,10 +696,10 @@ make_new_heap(Oid OIDOldHeap, Oid NewTableSpace, bool forcetemp,
*
* If the relation doesn't have a TOAST table already, we can't need one
* for the new relation. The other way around is possible though: if some
* wide columns have been dropped, AlterTableCreateToastTable can decide
* wide columns have been dropped, NewHeapCreateToastTable can decide
* that no TOAST table is needed for the new table.
*
* Note that AlterTableCreateToastTable ends with CommandCounterIncrement,
* Note that NewHeapCreateToastTable ends with CommandCounterIncrement,
* so that the TOAST table will be visible for insertion.
*/
toastid = OldHeap->rd_rel->reltoastrelid;
@@ -714,7 +714,7 @@ make_new_heap(Oid OIDOldHeap, Oid NewTableSpace, bool forcetemp,
if (isNull)
reloptions = (Datum) 0;
AlterTableCreateToastTable(OIDNewHeap, reloptions);
NewHeapCreateToastTable(OIDNewHeap, reloptions, lockmode);
ReleaseSysCache(tuple);
}