Guid primary key

1、Guid Algorithm ( or UUID Algorithm ) Generate a globally unique Id. Suitable for distributed systems , It is very simple to merge multi database data .
advantage ： Simple , High concurrency , Globally unique
shortcoming ： Large disk space

2、Guid Value discontinuity . Use Guid When type is used as primary key , Cannot set primary key as clustered index . Because the clustered index saves the primary key in order , So with Guid Poor primary key performance .