On May 26, 2010, at 1:33 PM, Dan Ellis wrote: > On May 26, 9:43 am, Michael Bayer <mike...@zzzcomputing.com> wrote: >> You can expire the attribute manually ahead of time if you want it to reload >> its value (should be fine within after_commit). > > No, it seems that in after_commit the newly added instance is not yet > in session.identity_map, so session.expire throws an exception: > "InvalidRequestError: Instance '<Story at 0x102e46ad0>' is not > persistent within this Session". At this point I'm confused. Why would > it not be persistent after a commit? (If I remove the extra code, the > Story is persisted just fine, so it's not like the transaction is > failing without the extension.)
its in the identity map after the flush succeeds, which is well before after_commit() is called. However, you can't really use the Session itself for database access inside of after_commit(). There is information on this available here: http://www.sqlalchemy.org/trac/wiki/UsageRecipes/UniqueSession . Here, your after_commit() hooks start fresh with a new session. If you want to use the state of objects from the parent session in the new session without reloading from the new transaction, use merge(..., load=False). -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalch...@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.
