Hi all,
We are going to be using Hibernate in a new project and were going to use the UUID generator to create our keys, however I was reading a bit of documentation showing an example:

http://www.hibernate.org/hib_docs/refer ... start.html

Which states:

Is there any good reason behind this?? It would be nice to know at this early stage in development!

Cheers,
Birju

I might think that there would be some sort of performance decrease with using UUIDs, although I've never seen very concrete numbers to say how much of a decrease it would be.

We looked at using UUIDs in order to generate IDs on object creation and then simply use those for our equals() and hashcode() implementations as they would never change. i.e. they'd be set when the object is created and then persisted and retrieved from the DB.

Just never got around to doing it or to doing some concrete testing of our own. Hell, we've still got some composite keys that we wanted to gut from day 1 out of the model that just haven't happened yet either.