now()

lesson

postgres sqlalchemy job-queue ordering now()

232 tok

Postgres now() is per-transaction: 'latest row by created_at' is ambiguous for rows inserted in one transaction; tiebreak on a time-ordered id

Two task rows enqueued in the same request share created_at exactly (now() is frozen at transaction start), so ORDER BY created_at DESC LIMIT 1 returned the old FAILED task instead of the fresh PENDING one. Add the primary key (sequence or time-ordered id) as a secondary sort.

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