Sequential GUID in Linq-to-Sql?

Question

I just read a blog post about NHibernate\'s ability to create a GUID from the system time (Guid.Comb), thus avoiding a good amount of database fragmentation. You could call

Answer 1

COMBs are generated the following way:

DECLARE @aGuid UNIQUEIDENTIFIER

SET @aGuid = CAST(CAST(NEWID() AS BINARY(10)) + CAST(GETDATE() AS BINARY(6)) AS UNIQUEIDENTIFIER)

Which transcribed into C# would look like this:

    public static unsafe Guid CombGuid()
    {
        Guid guid = Guid.NewGuid();
        byte[] bytes = guid.ToByteArray();
        long ticks = DateTime.Now.Ticks;
        fixed( byte* pByte = bytes )
        {
            int*    pFirst  = (int *)(pByte + 10);
            short* pNext    = (short*)(pByte + 14);
            *pFirst = (int)(ticks & 0xFFFFFF00);
            *pNext  = (short)ticks;
        }

        return new Guid( bytes );
    }