Database Basics
📌 Covered in this chapter:
SQL vs NoSQL · Primary/Foreign Keys · Relationships · CRUD · Transactions
Core relational database concepts every Node.js backend developer needs: SQL vs NoSQL, tables, keys, relationships, and transactions.
1Database Basics — What You'll Learn
Core relational database concepts every Node.js backend developer needs: SQL vs NoSQL, tables, keys, relationships, and transactions.
Here's everything this chapter covers, in the order you'll learn it:
- What a database is
- SQL vs NoSQL databases
- Tables, rows and columns
- Primary keys
- Foreign keys
- One-to-many and many-to-many relationships
- CRUD operations
- Indexes for faster lookups
- Transactions (atomic operations)
- Database security basics
- Connection pooling
2Best Practices & Common Pitfalls
💡 Key things to remember:
- SQL databases (PostgreSQL, MySQL) enforce a fixed schema and strong relationships; NoSQL databases (MongoDB) offer flexible, document-based schemas.
- A transaction groups multiple operations so they either ALL succeed or ALL fail together — critical for things like money transfers.
❓ Frequently Asked Questions (FAQ)
Q What's the most important thing to understand about database basics?
Focus on: SQL vs NoSQL · Primary/Foreign Keys · Relationships · CRUD · Transactions. These are the core building blocks this chapter's examples are built around, and they show up repeatedly in later chapters of this course.
Q Do I need external npm packages for database basics?
Only where explicitly shown in the code examples above (like Express, Zod, or Socket.IO) — otherwise, this chapter relies entirely on Node.js's own built-in capabilities.