GUID COMB strategy in EF

Question

Is there any way to implement the Guid COMB identity strategy for objects in the new Entity Framework 4.1 using the CodeFirst design? I thought setting the StoreGeneratedPattern would work, but it still gives me normal GUIDs.

Answer 1

Why worry about defaults for Guid columns in the database at all? Why not just generate the Guid on the client like any other value. That requires you have a method in your client code that will generate COMB-like guids:

public static Guid NewGuid()
{
    var guidBinary = new byte[16];
    Array.Copy( Guid.NewGuid().ToByteArray(), 0, guidBinary, 0, 8 );
    Array.Copy( BitConverter.GetBytes( DateTime.Now.Ticks ), 0, guidBinary, 8, 8 );
    return new Guid( guidBinary );
}

One of the advantages of the Guid is specifically that you can generate them on the client without a round trip to the database.