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Update collations-and-case-sensitivity.md #4466

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Update collations-and-case-sensitivity.md #4466

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2 changes: 1 addition & 1 deletion entity-framework/core/miscellaneous/collations-and-case-sensitivity.md
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Expand Up @@ -58,7 +58,7 @@ Note that some databases allow the collation to be defined when creating an inde

In .NET, string equality is case-sensitive by default: `s1 == s2` performs an ordinal comparison that requires the strings to be identical. Because the default collation of databases varies, and because it is desirable for simple equality to use indexes, EF Core makes no attempt to translate simple equality to a database case-sensitive operation: C# equality is translated directly to SQL equality, which may or may not be case-sensitive, depending on the specific database in use and its collation configuration.

In addition, .NET provides overloads of [`string.Equals`](/dotnet/api/system.string.equals) accepting a [`StringComparison`](/dotnet/api/system.stringcomparison) enum, which allows specifying case-sensitivity and a culture for the comparison. By design, EF Core refrains from translating these overloads to SQL, and attempting to use them will result in an exception. For one thing, EF Core does know not which case-sensitive or case-insensitive collation should be used. More importantly, applying a collation would in most cases prevent index usage, significantly impacting performance for a very basic and commonly-used .NET construct. To force a query to use case-sensitive or case-insensitive comparison, specify a collation explicitly via `EF.Functions.Collate` as [detailed above](#explicit-collations-and-indexes).
In addition, .NET provides overloads of [`string.Equals`](/dotnet/api/system.string.equals) accepting a [`StringComparison`](/dotnet/api/system.stringcomparison) enum, which allows specifying case-sensitivity and a culture for the comparison. By design, EF Core refrains from translating these overloads to SQL, and attempting to use them will result in an exception. For one thing, EF Core does not know which case-sensitive or case-insensitive collation should be used. More importantly, applying a collation would in most cases prevent index usage, significantly impacting performance for a very basic and commonly-used .NET construct. To force a query to use case-sensitive or case-insensitive comparison, specify a collation explicitly via `EF.Functions.Collate` as [detailed above](#explicit-collations-and-indexes).

## Additional resources

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