How do I scale a database?

Step by step:

1. Indexes on columns you filter and join by — the biggest, cheapest win
2. Fix slow queries — avoid fetching far more data than you need; paginate
3. Connection pooling (PgBouncer / Supabase pooler) so many app servers share connections
4. Caching for frequently read data
5. Read replicas for reporting and read-heavy traffic
6. Partitioning very large tables (e.g. by month)
7. Sharding — splitting data across servers — only at very large scale

Reejan does PostgreSQL query analysis and index optimisation in production.