I want my application to work under 2 databases: main remote db and local backup db. Do I have to implement it on my own or hibernate implements such mechanism (f.i. synchronizing dbs' content)?
thnx in advance.

you will need two separate HibernateManagers for each database with a different configuration file for each database.

I already have. The problem is it needs synchronization. Remote db would be used by many instances of the application, each of which has its own local db. Therefore, any operation on dbs needs copying from remote db to local db thos resources, which are not updated/created on local db. Particulary I found it hard to copy collections. So, are there any already created classes for that? I don't want to reinvent the wheel...
Thnx for response.

I haven't tried this ... but it should work ...

Add an additional session-factory to your hibernate.cfg.xml file.

No extra files needed.

i have never tried to accomplish transaction management across different databases using hibernate. but i have done it using transaction management using Resin 3.x. does a pretty good job.

I don't see why, if you use a class like
HibernateUtil in the reference documentation to create
your connections, you should have any sychonization issues.

well, i guess i am not brave enough to take that chance in synchronizing between 2 databases. considering that i just had to undertake a project to do that, i should say that i am in a slightly better position to make that call because we had to take into account rollbacks etc across two separate sessions. additionally, the number of rows being synched was in the 1000s. so there were quite a few factors that went into that decision.