Database Migration
Process of making controlled changes to database schema or content.
Definition
Database migration is the process of making controlled, versioned changes to database schema or content. Migrations enable evolving database structure alongside application code while maintaining data integrity and enabling rollback.
Migration tools track which changes have been applied to each environment, ensuring consistency. Well-managed migrations enable continuous database evolution without manual coordination or risky direct modifications.
Why It Matters
Applications evolve, and databases must evolve with them. Migrations provide a safe, repeatable process for database changes that prevents the chaos of ad-hoc modifications.
For development teams, migration discipline is essential for sustainable database management.
Examples in Practice
A migration adds a new column with a default value, then backfills data before enabling the feature that uses it.
Rollback migrations are tested before production deployment, ensuring quick recovery if issues arise.
Migration history tracks exactly what changes have been applied to each environment, preventing drift.