[Zope-dev] ZODB with twisted web.

I am checking out how to use ZODB with twisted web. I thought that I would have the DB instance globally accesible and call the open method to get a connection on each request. I thought that if I use connection.getTransaction().commit() before sending the response I will commit on the connection for that request. Is this necesarily true when using twisted web because it is single threaded and it seems that ZODB finds the correct transaction by checking the thread. I am a bit confused here and would rather like to avoid having one request commit changes for another request.