Have you worked with composite indexes in databases?

Composite indexes in databases are indexes that are created on multiple columns of a table simultaneously. They help speed up queries that filter or sort data based on a combination of these columns.

For example, if you have a table with fields first_name and last_name, and you frequently run queries with a WHERE condition on both fields, creating a composite index on (last_name, first_name) will allow the database to find the required records faster.

In Java applications, experience with composite indexes is usually related to using ORM (e.g., Hibernate), where you can specify composite indexes through annotations or XML configuration to optimize database queries.