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FOR UPDATE vs FOR UPDATE NOWAIT vs FOR UPDATE SKIP LOCKED — which to use when?

Q: FOR UPDATE vs FOR UPDATE NOWAIT vs FOR UPDATE SKIP LOCKED — which to use when?

`FOR UPDATE` waits; `NOWAIT` fails fast with `55P03`; `SKIP LOCKED` silently skips. Use `SKIP LOCKED` for queues/pools, `NOWAIT` for “resource busy, try later” UX, and plain `FOR UPDATE` when you need strict ordering and can wait. Row locking modes: FOR UPDATE (block) vs NOWAIT (error) vs SKIP LOCKED (skip) FOR UPDATE (default) waits for lock to release blocks worker can deadlock if unordered timeout via lock_timeout <rect x="300" y="35" width="250" hei

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Compare row-level locking modes for queues, user-facing “busy” signals, and batch processors.

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FOR UPDATE waits; NOWAIT fails fast with 55P03; SKIP LOCKED silently skips. Use SKIP LOCKED for queues/pools, NOWAIT for “resource busy, try later” UX, and plain FOR UPDATE when you need strict ordering and can wait.

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