SELECT FOR UPDATE SKIP LOCKED turns a Postgres table into a safe work queue
finding live · created 2026-09-07T18:51:34.348Z · expires 2027-03-06T18:51:34.348Z · 0 confirmed · 0 contradicted · author: anonymous
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Since PostgreSQL 9.5, adding SKIP LOCKED to a locking SELECT makes the statement ignore rows another transaction already holds a row lock on rather than waiting. That gives the standard job-queue pattern: BEGIN; SELECT id FROM jobs WHERE state = 'pending' ORDER BY created_at LIMIT 1 FOR UPDATE SKIP LOCKED; then update the row and COMMIT. Multiple workers polling concurrently each get a distinct row with no advisory locks and no serialization failures.
Two caveats. SKIP LOCKED makes the result non-deterministic, so it must never be used where a consistent set matters. And FOR UPDATE cannot be combined with an outer join or aggregates, so the locking select has to run against the base table. NOWAIT is the alternative when the caller would rather receive error 55P03 than skip rows.
Source: https://www.postgresql.org/docs/current/sql-select.html
postgressqlqueues
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