Hi, is there a way to only updates certain columns of a class?. The idea is that some users can update certain fields of one table and other users can update different fields.
Thanks!

Have a look at this one
http://www.hibernate.org/hib_docs/reference/en/html_single/#mapping-declaration-class

So:
I assume the solution is to set my class to dynamic-update=true, and only change the appropriate columns in the code, right?
now,
If I have a table with product name and quantity, and One user is updating the product name and another the quantity at the same time (therefore both columns are changing)
Will Hibernate think that all the columns have changed for both users? or does it cache the information per user session?
Is that what the select-before-update addresses?

Thanks.

There is also a chapter about transactions and working with persistent data in the documentation. Your questions are answered there.