Database Design Schema Design Principles Normalization Guidelines Denormalization for Performance Index Design Common Index Patterns Index Analysis Migration Patterns Safe Migration Template Zero-Downtime Migrations Query Optimization EXPLAIN Analysis Common Optimizations Constraints & Data Integrity Best Practices - Use UUIDs for public-facing IDs, SERIAL/BIGSERIAL for internal - Always add and timestamps - Use soft deletes ( ) for important data - Design for eventual consistency in distributed systems - Document schema decisions in migration files - Test migrations on production-size data b…