Hello

After reading thru the Reference Doc and Hibernate in Action I'm still a bit unsure regarding the usage of SessionFactory and Session.

Assuming I have a WebApplication (basically a servlet, created with SAP's WebDynpro technology) running unmanaged in an J2EE Application Server (SAP WebAS). This application will be used (hopefully) by many people concurrently.

My question now is: should I create exactly one instance of SessionFactory for my application and Session instances for each caller? If yes - does this (singleton SessionFactory) affect the caching or the result of queries created from Session instances?

OR should I have a SessionFactory for each user that calls my application?

Thanks in advance.

You should use at most one factory per web application, and one session for each request. I don't know what do you mean on "affect", but the secondary cache which is also used to cache queries is indeed a factory level thing.

You can use more than one SessionFactory in your web application, but that is if you use more than one database.

See the reference documentation (section 3.2):

http://www.hibernate.org/hib_docs/reference/en/html/session-configuration.html#configuration-sessionfactory