Issue with DataGrid and Filtering on computed property

Radzen Blazor Studio
1

Hi,

as described in Databases | Radzen Blazor Studio, I have created a computed property to join the columns "FirstName" and "LastName" to one single computed property which I use for a GridColumn.

This works as expected and the Grid shows the computed colmn values.

Now, when I use filtering on that column, I get an exception:

p.FullName.Contains("test"))' could not be translated. Additional information: Translation of member 'FullName' on entity type 'Customer' failed. This commonly occurs when the specified member is unmapped.

First, I thought this was due to the fact that I forgot to add [NotMapped] to the property, but even after I added this attribute, I still get this error. How can use filtering on a computed property?

Thanks for your help!

2

You cannot translate such property to SQL server since it's not part of the database. You can use ToList() before assigning Data to filter in-memory.

1 Like
3

You can also check EF's built-in support for computed columns: Generated Values - EF Core | Microsoft Learn

To try that you would need a partial class for the generated DBContext and implement the OnModelBuilding partial method.

public partial class MyContext
{
    partial void OnModelBuilding(ModelBuilder builder)
    {
        modelBuilder.Entity<Person>()
               .Property(p => p.FullName)
               .HasComputedColumnSql("[FirstName] + '  ' + [LastName]");
    }
}
1 Like
4

Thanks a lot for that hint!