On Mar 20, 2007, at 11:52 AM, Michael Bayer wrote:
> however, this is not using two phase commit, which means that if one > commit fails, all previous commit's stay committed. if you want true > two phase commit I'd look into Zalchemy which has this feature. actually i should correct myself - technically the commit strategy inside of SessionTransaction is more or less equivalent to what Zalchemy is doing right now - when you say trans.commit(), flush() will be called on the underlying session which will issue SQL to all involved databases. *then* it will go through and commit each database individually. since all SQL has been issued, its usually* the case that any exceptions that would have been raised have been raised already, and the commits are guaranteed** to succeed. * if you have your database set up to defer constraint checking until commit, then this wont work; exceptions will all get thrown at the COMMIT phase. zalchemy doesnt solve this either. ** "guaranteed" as close as we can get without accessing a true two- phase API on the database itself, which AFAICT is not possible with DBAPI. also if constraint checking is deferred until commit, like above the whole strategy fails. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalchemy@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~----------~----~----~----~------~----~------~--~---
