Performance value of COMB guids

Question

Jimmy Nilsson discusses his COMB guid concept here. This concept is popular in NHibernate, among other circles, for its supposed performance value over standard GUIDs which

Answer 1

Your code for generating new GUIDs isn't correct. For each row, it's creating a very different number (you call NEWID() for each row). You need to keep most of the GUID the same.