Not a competition. A choice of tools.
Direct answer
SQL databases store data in tables with a fixed structure and relationships, and you query them with SQL. NoSQL databases use flexible models such as documents or key-value pairs. Choose SQL for structured data with relationships and strong consistency, and NoSQL when data is flexible or you need specific scaling patterns.
Comparison
| SQL | NoSQL | |
|---|---|---|
| Structure | tables and schemas | documents, key-value, graph |
| Relationships | joins | often embedded or manual |
| Query language | SQL | varies |
| Consistency | strong by default | varies |
| Examples | PostgreSQL, MySQL, SQLite | document and key-value stores |
When to choose which
SQL: accounting, orders, users, anything with relationships and reports. NoSQL: flexible content, caches, event data and some very large-scale workloads.
Many apps use both
A relational database for core data and a key-value store for caching is common.
Where Teyro fits
Teyro's SQL and Databases for Beginners course turns this into short lessons you can play in a few minutes a day. It has 50 lessons, and you can start free.
The bottom line
Learn SQL first. It is the foundation.
