I am migrating a project that uses hibernate/spring to use the postgresql db. Currently, I am using hsqldb and I have implemented the hibernate version control.

I am new to postgresql, but it appears to have it's own sort of versioning system built in, MVCC. Now could someone explain to me how this will fit in with the hibernate versioning system. Is the postgres system at a lower level?

Will using both systems create a performance issue or does hibernate leverage the postgresql versioning system so they don't double up on this?

What is the best practice here? Is it at all advised to turn off the postgresql mvcc if i use the hibernate versioning (not even sure if this is possible)?

Essentially do the two versioning systems play nice together and is there any best practices i should be aware of when combining the systems?

PostgrSQl MVCC is an internal architecture approach to minimise the requirement of using Hard locks to maintain ACID principles. Other DBs, such as Oracle and others, use this technqiue as well. You only need to know that it works well (and the approach scales better). Hibernate versioning is there to help implement Optimistic locking. They are not (generally) related at all.