Never use spring.jpa.hibernate.ddl-auto=update in production. It’s unpredictable, irreversible, and can corrupt data. Flyway gives you version-controlled, audited, reproducible schema changes. Why Flyway? Every database change runs as a versioned SQL script. Flyway tracks which scripts have run in a flyway_schema_history table. When the app starts: Flyway reads all migration files Checks which have already run (by checking the history table) Runs any new ones, in order If the current state doesn’t match the expected state → fails fast Benefits: