What is the N+1 query problem in Flask-SQLAlchemy?

What is the N+1 query problem in Flask-SQLAlchemy?

The N+1 query problem occurs when an application makes one query to retrieve a list of items and then makes an additional query for each item to retrieve related data. This can lead to performance issues.

How can I avoid the N+1 problem in my application?

You can avoid the N+1 problem by using eager loading with the joinedload or subqueryload options in SQLAlchemy. This allows you to load related data in a single query.

Can you give me an example of using eager loading?

Sure! Here's an example: session.query(Parent).options(joinedload(Parent.children)).all() will load all parents and their children in one query.

What are the performance implications of the N+1 problem?

The N+1 problem can significantly slow down your application, especially with large datasets, as it increases the number of database queries.