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Slow EF Core queries rarely need a rewrite of your whole app — they need diagnosis and a short list of fixes that actually change plans.

This cookbook is for mid-level .NET developers shipping ASP.NET Core APIs. You get problem → diagnosis → fix → before/after patterns for N+1, projections, tracking costs, indexes, migrations, and bulk work. Recipes are copy-paste oriented, with antimatter “don’t do this” callouts.

You’ll learn how to:

Measure first (logging, interceptors, profilers)
Eliminate classic N+1 and lazy-loading traps
Use projections, AsNoTracking, and split queries deliberately
Shape queries so indexes help instead of hurt
Review PRs with a performance checklist

Written with AI assistance under author direction. Verify snippets against your EF Core / .NET version before production use.

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Kick off your book project, get started with GhostAI, get better at marketing, or spend the day doing all three! Free live workshops on Zoom. Saturday, June 27, 2026.

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