I think you have misunderstood this feature. The
index attribute for properties and other things are not really used by the Hibernate core. As far as I know, it is only used by the schema generation tool to create indexed column(s) in the database. So, if you are planning to use the schema generation tool, you may want to put
index attributes on some properties. If you already have an existing database with the proper indexes created, I don't think it matters if you have the
index attribute or not. Except maybe for documentation purposes. You can find more information about the schema generation tool here:
http://www.hibernate.org/hib_docs/v3/re ... guide.html