Andreas Joseph Krogh <andreas@xxxxxxxxxx> writes: > I have this "dequeue" query which is working: > Â > select qe.entity_id, qe.queue_id, qe.sequence_id, qe.tx_id , qe.payload_string > fromorigo_queue_entry qe WHERE qe.queue_id = 2 AND pg_try_advisory_xact_lock( > sequence_id) LIMIT 1 FOR UPDATE ; > I'm not sure is this is guaranteed to lock in ASC-order on column sequence_id, > is it? No. You could possibly do SELECT...ORDER BY...FOR UPDATE in a subquery and do the pg_try_advisory_xact_lock call in the outer query. It might take some fooling around to get a plan that doesn't lock more rows than necessary; EXPLAIN is your friend. regards, tom lane -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
