Learning path
Safe Schema Migrations
Lock-safe DDL, CONCURRENTLY, expand/contract and zero-downtime rollouts.
backend, platform · Advanced · 2 courses · 12 simulations
The path
Courses, then incidents
Work through the courses, then practise the incidents — each step links to its page.
- Course Safe Schema Changes: Columns and Constraints →
- Course Zero-downtime Migrations →
- migrations-releases ALTER TABLE locks production →
- migrations-releases CREATE INDEX without CONCURRENTLY →
- migrations-releases Failed CREATE INDEX CONCURRENTLY →
- migrations-releases Bad nullable column rollout →
- migrations-releases Backward-incompatible migration →
- migrations-releases Expand/contract migration →
- migrations-releases Migration applied to the wrong database →
- migrations-releases Migration applied to one tenant only →
- migrations-releases Schema drift between tenant databases →
- migrations-releases App connected to a stale shadow database →
- locks-transactions CREATE INDEX without CONCURRENTLY blocks writes →
- locks-transactions Long transaction blocks a DDL migration →