O'Reilly logo
  • Dustin Waybright thinks this is interesting:

one of the main benefits of GUIDs is the fact that they can be generated anywhere and not conflict across time and space. You can generate GUIDs not just in SQL Server using the NEWID function, but anywhere, using APIs.


Cover of Training Kit (Exam 70-461): Querying Microsoft® SQL Server® 2012


GUIDs are handy as a table identifier because they can be created by outside applications writing the database, such as an application programming interface (API). The probability of a non-unique GUID is negligible. If everyone on earth had 600,000,000 GUIDs, there would be one duplicate.