Database

A database stores and retrieves structured data. Schema changes can affect many parts of a service.

A database stores and retrieves data such as users, posts, orders, or sensor values. Web sites often use databases such as MySQL or PostgreSQL.

Unlike text edits, database schema changes can affect many pages and features, so backups and verification are important.

✅ Why it matters

• Organizes service data systematically
• Supports features such as search, analytics, and login

⚠️ Limits and debates

• Poor design can become expensive to fix
• Changes without backups can be hard to recover