Database Migrations

Plan additive, zero-downtime schema migrations with rollout, backfill, and rollback awareness. Use when renaming columns, backfilling data, or shipping risky database changes.

HoangNguyen0403 Updated 542 repo stars

File contents

Database Migrations

Priority: P0 (CRITICAL)

Use expand -> backfill -> contract for risky changes.

Rules

  • Ship additive schema first.
  • Backfill with resumable logic and visibility.
  • Flip reads/writes only after new shape is populated.
  • Drop old columns or indexes in a later safe step.

Verify

  • Migration can run without taking the app offline.
  • Backfill ownership, batching, and monitoring are defined.
  • Rollback or pause strategy exists.
  • Old and new code paths can coexist during rollout.

Anti-Patterns

  • No destructive one-shot rename: expand and migrate first.
  • No hidden backfill: long data moves need explicit plan and observability.
  • No app deploy coupling by accident: schema and code rollout order must be clear.

References

HoangNguyen0403/agent-skills-standard/tree/main/skills/database/database-migrations commit 24ad2a34b2

Frequently asked questions

npx skillmds@latest add hoangnguyen0403/database-migrations