Find and fix the N+1 queries hiding in a nested API response

My endpoint returns a list of orders with their customers, and it works, but the database log shows one extra query per order.

Beginner to intermediateRead 6 minDoing: under an hour6 steps

▶ Start

What you'll have at the end

The same endpoint response using 2 queries total instead of one per row, confirmed by counting queries in the log

Before you start

You need

A working endpoint that already queries a list of orders through SQLAlchemy and returns each one with its customer's name, plus the ability to turn on your own database connection's query logging.

Not covered

An N+1 coming from a raw SQL loop instead of the ORM's own relationship loading; that needs a different fix than a loader option.

Leans on

6 steps

Where to go next

Know when to drop to raw SQL

when even a join or a batch isn't fast enough on its own, that's the next place to look, not another loader option.

Checked 18 Aug 2026

Part of the ORM and Database Abstraction Tools cookbook