What are database indexes and why are they important?

What are database indexes and why are they important?

Database indexes are data structures that improve the speed of data retrieval operations on a database table. They work like an index in a book, allowing the database to find data without scanning every row.

How do indexes affect database performance?

Indexes can significantly enhance performance by reducing the amount of data the database needs to scan. However, they can also slow down write operations, as the index must be updated whenever data is modified.

Can you explain the different types of indexes?

Sure! Common types of indexes include B-tree indexes, hash indexes, and full-text indexes. Each type serves different use cases and has its own advantages.

When should I use an index?

You should use an index when you have large tables and frequently query specific columns. It's particularly useful for columns used in WHERE clauses, JOINs, and ORDER BY statements.