ClickHouse is a column-oriented OLAP database that scans hundreds of millions of rows in seconds. DaoDao uses it to record user behavior events for the AI recommendation engine's feature engineering, letting PostgreSQL focus on transactional data.
D1 is Cloudflare's serverless SQLite database that binds directly to Workers, supports full SQL (JOINs, transactions), and handles automatic backups. It's well-suited for small-to-medium relational data needs — NobodyClimb uses it as its primary database.
Prisma's schema-first design gives you versioned migrations, full TypeScript types on every query, and intuitive relation handling. The tradeoff is a learning curve and the inherent limits of any ORM abstraction — but for most TypeScript projects, it's a worthwhile deal.