Database 584 installs

Database Migration Patterns

by affaan-m/everything-claude-code

Database migration best practices for schema changes, data migrations, rollbacks, and zero-downtime deployments across PostgreSQL, MySQL, and common ORMs…

Skill content

Database Migration Patterns

Safe, reversible database schema changes for production systems.

When to Activate

- Creating or altering database tables

- Adding/removing columns or indexes

- Running data migrations (backfill, transform)

- Planning zero-downtime schema changes

- Setting up migration tooling for a new project

Core Principles

- Every change is a migration - never alter production databases manually

- Migrations are forward-only in production - rollbacks use new forward migrations

- Schema and data migrations are separate - never mix DDL and DML in one migration

- Test migrations against production-sized data - a migration that works on 100 rows may lock on 10M

- Migrations are immutable once deployed - never edit a migration that has run in production