N+1 Problem in Django Rest Framework
summary
Shows that N+1 appears in Django Rest Framework both in view querysets and serializer fields and that using select_related and prefetch_related actually fixes it. Uses an author/book/tag example API, detects problems with nplusone and Django Debug Toolbar, and measures dramatic improvements — e.g. authors endpoint drops from about 197 queries to 7, books from ~53 to 5 — demonstrating the change is real and effective in practice.
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chapters (13)
- 0:00Introduction
- 2:14Django Rest Framework
- 4:00N+1 problem in ORMs
- 8:18Example models
- 10:24N+1 in DRF views
- 12:58Serializer-level N+1
- 14:45Tools to detect N+1
- 18:42Solving N+1 with select_related
- 21:19Solving N+1 with prefetch_related
- 23:50DRF recommendations
- 24:54Performance impact
- 27:03References
- 28:09Q&A
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