Database Migrations Zero Downtime

Use When

• Changing schema used by active production services
• Migrating large tables or high-traffic query paths

Workflow

1. Choose compatible migration strategy (expand, migrate, contract).
2. Add backward-compatible reads and writes.
3. Run data backfill in controlled batches.
4. Verify application compatibility across versions.
5. Remove old schema only after rollout validation.

Required Checks