Create and manage database migrations with reversible changes, zero-downtime deployments, and proper version control. Use this skill when creating database migration files, modifying database schemas, adding or removing tables or columns, creating indexes, or managing database versioning. When working with migration files (e.g., `*_migration.rb`, `*.migration.ts`, `alembic/versions/*.py`), schema changes, or database rollback procedures. When implementing backwards-compatible database changes or separating schema migrations from data migrations.