I need Hibernate to select the value for a field mapped as a property from a sequence when inserting, just like it does for id's.
I can't use triggers on the DB, so mapping with generated="insert" is not an option. Just Hibernate doing "select next_val('some_sequence')" would do. Is it possible?

Thanks!

Yes. use 'formula' property for that attribute mapping instead of column like:
formula="SELECT ..." the select to extract the next value from sequence.

Sorry, I think it is wrong what I said before.
It doesn't work like this.
Maybe to have a method into your code that retrieve the next value from sequence and setting the property with this value before saving the object.
(and having maybe update="false" on that property)

Yes, I could do something like that. However, I've found that apparently it's possible to define custom insert sql for mapped classes, with a <sql-insert> tag on the mapping file. I haven't tried it yet, but I'm thinking that maybe replacing the "?" corresponding to the pk with something like 'select next_val from _sequence_' might work.

Anyway, thanks for replying crista_drg!

Yes, it could be a solution, I talked about it into:
http://forum.hibernate.org/viewtopic.php?p=2365993