Previously Michael Bayer wrote: > > > On Feb 26, 2009, at 1:29 AM, 一首诗 wrote: > > > > > The document says: > > > > ==================================================== > > Expunge removes an object from the Session, sending persistent > > instances to the detached state, and pending instances to the > > transient state: > > > > ==================================================== > > > > I hoped that if an instance was expunged from a session, I might use > > it safely as a container of some temp data without fearing trigger any > > database query. > > > > But I found that if an object is 'expunge'd , it's properties will > > not be accessible anymore. > > > > So, when should we use expunge? Or it is kept for sqlalchemy inner > > use only? > > you can reattach the object to a session later if you need it to be > part of a transaction again. it can be used for caching scenarios, > for example. But I agree most reasonable applications probably won't > use expunge() very much.
What happens if you do not call expunge on it, but pickle the object in a cache, load it later and then merge it? Wichert. -- Wichert Akkerman <wich...@wiggy.net> It is simple to make things. http://www.wiggy.net/ It is hard to make things simple. --~--~---------~--~----~------------~-------~--~----~ 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 sqlalchemy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~----------~----~----~----~------~----~------~--~---
