After reading many posts and Googling around, I have been unable to come up with a good answer to what strategy is best when you need globally unique ids.

I've gathered that identity columns require two database transactions per insert. Also, from several Hibernate team members that using UUID is not a good strategy due to performance issues.

Can someone point me to some more documentation, not necessarily Hibernate related, that can elaborate on these concepts?

Thanks!

This is not exactly an answer for you but are you sure you want globally unique identifiers or database wide unique identifiers will be good enough for you?


Farzad-

In most cases, database wide will be sufficient. However, I'm looking to a) learn something and b) be able to scale out without headaches. Basically, I would like to get a firm understanding of exactly when each id generation method is most appropriate or when it makes sense to develop some other (homegrown) technique.

I have answered at least one of my questions, a good explanation of UUID generation.

http://www.iwombat.com/whitePapers/UniqueIdentifiers.html