WAL Archiving and Point-in-Time Recovery
Replicas copy your mistakes instantly, so a bad DROP TABLE hits every standby too.
Point-in-Time Recovery is a rewind button: start from an older full backup, then replay the saved change-log up to the exact second before the mistake. You land on the database as it was just before things went wrong.
Pro members see the rest of this lesson
- A 4-step state diagram: Archive → Mistake → Replay → Promote
- The full mechanism: what PostgreSQL does internally, in source terms
- 2 SQL queries you can run, each labelled by how it was verified
- 1 transcript captured on PostgreSQL 17.10
- The closing insight, the mistake it prevents, and what it changes in your work
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Check it against the source2 citations in postgres/postgres · file, symbol and line verified on REL_17_STABLE
Primary symbol: RestoreArchivedFile · line 54
Primary symbol: PerformWalRecovery · line 1662
Anchored to postgres/postgres on REL_17_STABLE and cross-checked against the manual for PostgreSQL 15–18. Every query here was run and its output captured on a throwaway PostgreSQL 17.10 lab; corrections are noted inline. §26.3 Continuous Archiving and PITR in the official docs →
Connected
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What comes before, after, and alongside it.
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