How to Achieve Case-Sensitive Comparisons in LINQ to Entities?

Achieving Case-Sensitive Comparisons in LINQ to Entities

LINQ to Entities queries, like Thingies.First(t => t.Name == "ThingamaBob"), might not be case-sensitive by default. This is due to LINQ to Entities translating Lambda expressions into SQL, where case sensitivity relies on the SQL Server database's collation settings.

Database-Level Solution: Modifying Collation

The most efficient way to ensure case-sensitive comparisons is to alter the column's collation to a case-sensitive option. For instance, to make the Name column in the Thingies table case-sensitive, use this SQL command:

ALTER TABLE Thingies
ALTER COLUMN Name VARCHAR(25)
COLLATE Latin1_General_CS_AS

Client-Side Approach: Utilizing LINQ to Objects

If modifying the database collation isn't feasible, a client-side solution using LINQ to Objects provides an alternative. This involves an initial database query followed by an in-memory comparison using AsEnumerable(). Example:

Thingies.Where(t => t.Name == "ThingamaBob")
        .AsEnumerable()
        .First(t => t.Name == "ThingamaBob");

This performs the case-sensitive check in-memory after the initial database filtering. Note that this method might be less performant than the server-side collation change.

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