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Entity Framework Core–DateOnly and TimeOnly

Last week I had the pleasure to work with a team that started using Entity Framework Core for the first time. They had a lot of experience using NHibernate, so the concept of an ORM was not new. But it was interesting to see which things are obvious when switching to EF Core and which are not.

After a few hiccups the team was finally on a role and they were starting to add more and more features. A (last?) question I got was regarding the usage of the DateOnly and TimeOnly types. These types were introduced in .NET 6 and are a welcome addition next to the DateTime type.

The question was of course if we could use these types in combination with EF Core?

These type have been supported for several database providers (e.g. SQLite, MySQL, and PostgreSQL) since their introduction. Unfortunately for SQL Server, we had to wait for a recent release of a Microsoft.Data.SqlClient package. So starting from EF8 DateOnly and TimeOnly are supported for SQL Server as well.

Remark: If you cannot wait for the release of EF8, you can use the following NuGet package for EF Core 6 and 7: https://www.nuget.org/packages/ErikEJ.EntityFrameworkCore.SqlServer.DateOnlyTimeOnly

You don’t have to do anything special to use it, just create an Entity type and use properties of type DateOnly or TimeOnly:

More information

Using DateOnly and TimeOnly in .NET 6 - Steve Gordon - Code with Steve (stevejgordon.co.uk)

What's new in EF Core 8 | Microsoft Learn

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