Lesson 10 · 15 min
Zero downtime migrations
Expand and contract, new columns and indexes CONCURRENTLY, NOT VALID constraints and backfills in batches.
15 minLesson 10 of 10Practice includedAsk AI on any point
During a deploy the old and new versions of the app run at the same time. A migration that breaks the old version or locks a table for a minute means downtime. The rules below let you change the schema under load.
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