Thanks, that was exactly what I wanted! Everything I would want to remove would indeed be during that single request/response cycle. I've since learned I might be able to get the same effect by throwing an exception, but again, I'm lacking documentation and I don't know if I would have to catch it myself or what exception specifically to throw.
I would still welcome any information on locking a table (even though it's not actually required in my case). I understand your comment about slowing down the system, as well as deadlocks. Mike On Jul 30, 8:53 am, "Diez B. Roggisch" <[email protected]> wrote: > > -Are you telling me that I cannot roll back transactions unless I rip > > out the middleware? There's no accessible command to the middleware > > with TG2 as it ships? > > I think you want then is > > import transaction > > transaction.doom() > > That will mark an ongoing transaction as failed, and provoke a rollback on > middleware egress. > > > -How can I lock a table? I thought that was done by TG as well - that > > each call to a controller made the database safe to access. > > Nope. And it wouldn't be desirable, because that would mean that the system > would slowdown to a screeching halt, and automatic locking is likely to > create deadlocks. > > > > > -I actually do want to roll back *all* the previous transactions made > > in that sessions. It was an all-or-nothing scenario. If there's a > > single duplicate in that database, then I want to remove all of the > > new entries added during this call. I would expect rollback() > > wouldn't remove items already in the database from a previous call to > > the controller (which ends with a commit() as I understand it, perhaps > > in repoze.tm2 as you point out?) > > A transaction spans usually a request/response-cycle (this is the way the > system is set up, you'd have to manually alter a lot of things to make it > work different), and the very nature of transactions is that they are > isolated from each other. So if you have ten calls to the action, and > rollback the last, then you'd have still the work of the 9 successful ones in > the DB. > > Diez --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "TurboGears" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/turbogears?hl=en -~----------~----~----~----~------~----~------~--~---
