Databases · Junior · Question 47 of 75

What does 'durability' guarantee?

✓Correct answer: Once a transaction is committed, its changes survive a crash or power loss
2Data is stored forever and can't be deleted
3Queries never take longer than a second

Explanation

PostgreSQL writes changes to the write-ahead log (WAL) and flushes it to disk before confirming the commit. After a crash it replays the log.

Further reading

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