Optimizing Django ORM Queries: A Practical Guide to select_related and prefetch_related (opens in new tab)

1. Introduction Django's ORM is one of its greatest strengths. It abstracts away raw SQL, lets you express database operations in clean Python, and gets you productive fast. But that convenience comes with a hidden cost: if you're not deliberate about how you fetch related objects, you'll silently generate far more queries than you intend — and you won't notice until your app slows to a crawl in production. The most common culprit is the N+1 query problem: a pattern where fetching a list of N...