Database Implementation

Database migrations with Flyway use versioned SQL files (V001, V002, etc.) to version schema changes. Write migration scripts for table creation, columns, and constraints, then execute via ./gradlew flywayMigrate. Flyway tracks applied migrations and prevents re-execution, ensuring repeatable, reliable schema evolution.

Use flywayInfo to inspect migration history and status, and flywayClean to reset for testing. Plan rollback strategies within your migration scripts—undo procedures or separate rollback migrations. Test migrations in isolated environments before applying to production to guarantee success.

ORM mapping with frameworks like Exposed connects entity classes to relational tables through schema definitions and foreign keys. Define relationships (one-to-many, many-to-many) using junction tables and constraints. Pair ORM mappings with indexed columns and query optimization for maintainable, performant data models.

Indexing creates fast lookup paths on frequently queried columns; constraints enforce data integrity. Add indexes to foreign keys, primary keys, and search filters within migrations. Query optimization techniques combined with proper indexing reduce scan time and improve application responsiveness across large datasets.

Flyway executes SQL migrations on relational databases to create schemas, seed test data, and manage constraints. Each versioned migration is idempotent and repeatable, making it ideal for test environments. Combine migrations with rollback strategies to validate schema changes before production deployment.