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--
-- ADVISORY LOCKS
--
SELECT oid AS datoid FROM pg_database WHERE datname = current_database() \gset
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' AND database = :datoid
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' AND database = :datoid;
-- 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' AND database = :datoid;
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' AND database = :datoid
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' AND database = :datoid
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' AND database = :datoid;
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' AND database = :datoid
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' AND database = :datoid
ORDER BY classid, objid, objsubid;
-- releasing all session locks
SELECT pg_advisory_unlock_all();
SELECT count(*) FROM pg_locks WHERE locktype = 'advisory' AND database = :datoid;
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' AND database = :datoid
ORDER BY classid, objid, objsubid;
COMMIT;
SELECT count(*) FROM pg_locks WHERE locktype = 'advisory' AND database = :datoid;
-- 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' AND database = :datoid
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 database = :datoid;
-- .. 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' AND database = :datoid
ORDER BY classid, objid, objsubid;
SELECT pg_advisory_unlock_all();
SELECT count(*) FROM pg_locks WHERE locktype = 'advisory' AND database = :datoid;
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