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Overwhelming the IN Operator

Tariq Rasheed Al-Qaralleh recounts a customer problem:

In some cases, like when customers use Object-relational Mapping tools (ORM) Like Entity framework or LINQ, part of the code at the end will be converted to a TSQL executable statement.

For example, The LINQ with  .Where () method will be a TSQL Query with a Where clause :

Query Syntax and Method Syntax in LINQ (C#) | Microsoft Learn

Write LINQ queries in C# | Microsoft Learn

Read on for some of the practical consequences of doing this, including performance issues and possibly even runtime errors.

Tariq gives a couple examples of how to fix the issue, and a third possible fix is to pass in the IN clause as a table-valued parameter and join to that TVP.