Can I disable First Level Cache in Hibernate, if I want?
If yes how?
No, it's the default and there is no way to disable the first level cache.
One thing you can do is clear it everytime you query, but i don't really see the point.
The only situation that i can think of that could give problem is when you have a session where you fetch from db a lot of object for reading and you don't need them in cache. But even then you can query for single field instead of whole object to avoid caching it
NOPE, you can't.
You can have no interaction with the first level cache with StatelessSession. Read more about it in https://docs.jboss.org/hibernate/orm/5.2/userguide/html_single/chapters/batch/Batching.html