mirror of
https://git.postgresql.org/git/postgresql.git
synced 2024-10-04 05:36:52 +02:00
147 lines
4.0 KiB
MySQL
147 lines
4.0 KiB
MySQL
|
--
|
||
|
-- ADVISORY LOCKS
|
||
|
--
|
||
|
|
||
|
BEGIN;
|
||
|
|
||
|
SELECT
|
||
|
pg_advisory_xact_lock(1), pg_advisory_xact_lock_shared(2),
|
||
|
pg_advisory_xact_lock(1, 1), pg_advisory_xact_lock_shared(2, 2);
|
||
|
|
||
|
SELECT locktype, classid, objid, objsubid, mode, granted
|
||
|
FROM pg_locks WHERE locktype = 'advisory'
|
||
|
ORDER BY classid, objid, objsubid;
|
||
|
|
||
|
|
||
|
-- pg_advisory_unlock_all() shouldn't release xact locks
|
||
|
SELECT pg_advisory_unlock_all();
|
||
|
|
||
|
SELECT count(*) FROM pg_locks WHERE locktype = 'advisory';
|
||
|
|
||
|
|
||
|
-- can't unlock xact locks
|
||
|
SELECT
|
||
|
pg_advisory_unlock(1), pg_advisory_unlock_shared(2),
|
||
|
pg_advisory_unlock(1, 1), pg_advisory_unlock_shared(2, 2);
|
||
|
|
||
|
|
||
|
-- automatically release xact locks at commit
|
||
|
COMMIT;
|
||
|
|
||
|
SELECT count(*) FROM pg_locks WHERE locktype = 'advisory';
|
||
|
|
||
|
|
||
|
BEGIN;
|
||
|
|
||
|
-- holding both session and xact locks on the same objects, xact first
|
||
|
SELECT
|
||
|
pg_advisory_xact_lock(1), pg_advisory_xact_lock_shared(2),
|
||
|
pg_advisory_xact_lock(1, 1), pg_advisory_xact_lock_shared(2, 2);
|
||
|
|
||
|
SELECT locktype, classid, objid, objsubid, mode, granted
|
||
|
FROM pg_locks WHERE locktype = 'advisory'
|
||
|
ORDER BY classid, objid, objsubid;
|
||
|
|
||
|
SELECT
|
||
|
pg_advisory_lock(1), pg_advisory_lock_shared(2),
|
||
|
pg_advisory_lock(1, 1), pg_advisory_lock_shared(2, 2);
|
||
|
|
||
|
ROLLBACK;
|
||
|
|
||
|
SELECT locktype, classid, objid, objsubid, mode, granted
|
||
|
FROM pg_locks WHERE locktype = 'advisory'
|
||
|
ORDER BY classid, objid, objsubid;
|
||
|
|
||
|
|
||
|
-- unlocking session locks
|
||
|
SELECT
|
||
|
pg_advisory_unlock(1), pg_advisory_unlock(1),
|
||
|
pg_advisory_unlock_shared(2), pg_advisory_unlock_shared(2),
|
||
|
pg_advisory_unlock(1, 1), pg_advisory_unlock(1, 1),
|
||
|
pg_advisory_unlock_shared(2, 2), pg_advisory_unlock_shared(2, 2);
|
||
|
|
||
|
SELECT count(*) FROM pg_locks WHERE locktype = 'advisory';
|
||
|
|
||
|
|
||
|
BEGIN;
|
||
|
|
||
|
-- holding both session and xact locks on the same objects, session first
|
||
|
SELECT
|
||
|
pg_advisory_lock(1), pg_advisory_lock_shared(2),
|
||
|
pg_advisory_lock(1, 1), pg_advisory_lock_shared(2, 2);
|
||
|
|
||
|
SELECT locktype, classid, objid, objsubid, mode, granted
|
||
|
FROM pg_locks WHERE locktype = 'advisory'
|
||
|
ORDER BY classid, objid, objsubid;
|
||
|
|
||
|
SELECT
|
||
|
pg_advisory_xact_lock(1), pg_advisory_xact_lock_shared(2),
|
||
|
pg_advisory_xact_lock(1, 1), pg_advisory_xact_lock_shared(2, 2);
|
||
|
|
||
|
ROLLBACK;
|
||
|
|
||
|
SELECT locktype, classid, objid, objsubid, mode, granted
|
||
|
FROM pg_locks WHERE locktype = 'advisory'
|
||
|
ORDER BY classid, objid, objsubid;
|
||
|
|
||
|
|
||
|
-- releasing all session locks
|
||
|
SELECT pg_advisory_unlock_all();
|
||
|
|
||
|
SELECT count(*) FROM pg_locks WHERE locktype = 'advisory';
|
||
|
|
||
|
|
||
|
BEGIN;
|
||
|
|
||
|
-- grabbing txn locks multiple times
|
||
|
|
||
|
SELECT
|
||
|
pg_advisory_xact_lock(1), pg_advisory_xact_lock(1),
|
||
|
pg_advisory_xact_lock_shared(2), pg_advisory_xact_lock_shared(2),
|
||
|
pg_advisory_xact_lock(1, 1), pg_advisory_xact_lock(1, 1),
|
||
|
pg_advisory_xact_lock_shared(2, 2), pg_advisory_xact_lock_shared(2, 2);
|
||
|
|
||
|
SELECT locktype, classid, objid, objsubid, mode, granted
|
||
|
FROM pg_locks WHERE locktype = 'advisory'
|
||
|
ORDER BY classid, objid, objsubid;
|
||
|
|
||
|
COMMIT;
|
||
|
|
||
|
SELECT count(*) FROM pg_locks WHERE locktype = 'advisory';
|
||
|
|
||
|
-- grabbing session locks multiple times
|
||
|
|
||
|
SELECT
|
||
|
pg_advisory_lock(1), pg_advisory_lock(1),
|
||
|
pg_advisory_lock_shared(2), pg_advisory_lock_shared(2),
|
||
|
pg_advisory_lock(1, 1), pg_advisory_lock(1, 1),
|
||
|
pg_advisory_lock_shared(2, 2), pg_advisory_lock_shared(2, 2);
|
||
|
|
||
|
SELECT locktype, classid, objid, objsubid, mode, granted
|
||
|
FROM pg_locks WHERE locktype = 'advisory'
|
||
|
ORDER BY classid, objid, objsubid;
|
||
|
|
||
|
SELECT
|
||
|
pg_advisory_unlock(1), pg_advisory_unlock(1),
|
||
|
pg_advisory_unlock_shared(2), pg_advisory_unlock_shared(2),
|
||
|
pg_advisory_unlock(1, 1), pg_advisory_unlock(1, 1),
|
||
|
pg_advisory_unlock_shared(2, 2), pg_advisory_unlock_shared(2, 2);
|
||
|
|
||
|
SELECT count(*) FROM pg_locks WHERE locktype = 'advisory';
|
||
|
|
||
|
-- .. and releasing them all at once
|
||
|
|
||
|
SELECT
|
||
|
pg_advisory_lock(1), pg_advisory_lock(1),
|
||
|
pg_advisory_lock_shared(2), pg_advisory_lock_shared(2),
|
||
|
pg_advisory_lock(1, 1), pg_advisory_lock(1, 1),
|
||
|
pg_advisory_lock_shared(2, 2), pg_advisory_lock_shared(2, 2);
|
||
|
|
||
|
SELECT locktype, classid, objid, objsubid, mode, granted
|
||
|
FROM pg_locks WHERE locktype = 'advisory'
|
||
|
ORDER BY classid, objid, objsubid;
|
||
|
|
||
|
SELECT pg_advisory_unlock_all();
|
||
|
|
||
|
SELECT count(*) FROM pg_locks WHERE locktype = 'advisory';
|