Create and manage database schema migrations with reversible operations, zero-downtime deployments, and safe rollback strategies. Use this skill when writing database migrations for PostgreSQL, MySQL, SQLite, MongoDB, or any database system; when using ORMs like Prisma, Sequelize, TypeORM, ActiveRecord, Django ORM, or similar migration tools; when implementing schema changes (adding tables, columns, indexes, constraints); when performing data migrations or transformations; when creating indexes on large tables with concurrent options to avoid locks; when separating schema changes from data migrations for safer rollbacks; when implementing zero-downtime deployment strategies for high-availability systems; when versioning database schemas and managing migration order; or when working with database change management in production environments.