Database Migrations

This is a comprehensive reference for production database migrations across Postgres, MySQL, and popular ORMs like Prisma, Drizzle, Kysely, Django, and TypeORM. It covers the critical stuff that bites you in production: zero-downtime column renames using expand-contract patterns, concurrent index creation to avoid table locks, batched updates for large tables, and the absolute rule that you never edit a migration after it runs. The safety checklist alone (nullable columns, separate schema and data migrations, testing against production-sized data) is worth having open during code review. Especially useful if you're moving from "just run ALTER TABLE" to proper migration discipline, or if you've been burned by a migration that worked fine in dev but locked your production table for twenty minutes.

Install to Claude Code

npx -y skills add affaan-m/ecc --skill database-migrations --agent claude-code