How do you determine when to use SQL or NoSQL databases in a project?

The choice between SQL and NoSQL databases depends on the project requirements and data structure.

• SQL (relational databases) are suitable when data is strictly structured, integrity is important, and complex queries with JOINs are needed. For example, banking systems where transactional consistency is crucial.
• NoSQL is better used when data is unstructured or semi-structured, horizontal scaling and high write speed are required. For example, log storage, caching, systems with large volumes of data and fast access.

Example: if you have well-defined tables with relationships between them and ACID consistency is important, choose SQL. If the data is flexible, changes often, and scalability is important — NoSQL.