EFCore - Expression trees climbing

on YouTube ↗44m

" summary

60% live coding demos show how to build and inspect .NET expression trees with the raw Expression API, then use EF Core to translate them to SQL and expose pitfalls: string.Contains becomes LIKE and mixes with SQL three‑valued logic causing wrong results for NULLs. A dynamic OR over a list is assembled manually and then replaced with PredicateBuilder. A performance bug (compiling thousands of lambdas → ~3s) is fixed by a compiled static expression plus an ExpressionVisitor that replaces a parameter with a constant; also warns against storing expressions as record properties (ToString recursion).

AI-written summary · about

" chapters (5)

1. 0:00Introduction to Expression Trees
2. 8:59Manual Expression Tree Creation
3. 17:12Collections and Any/All Operations
4. 27:52Universal Conditions with Expression Trees
5. 42:57Summary and Q&A

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