What is the N+1 problem?

The N+1 problem occurs when working with databases and ORM, where one query is executed for the main entity (1), and then N additional queries are made — one for each related record. This leads to a significant decrease in performance due to the large number of queries.

For example, when loading a list of users and their orders, ORM might first query all users, and then for each user, a separate query for orders. Instead, it is better to use eager loading or JOIN to retrieve all data in one or a few optimized queries.