Alvaro Herrera <alvherre@dcc.uchile.cl> writes: > Several things. I think I wrote them along with my previous patch. The > visibility rules and the pg_clog protocol are what comes to mind > immediately. This is the difficult part. Difficult part? I think those are easy --- they are narrow and already solved-in-principle problems. What I do not understand is how you are going to handle error recovery and undo in general. Every single backend module that has any at-abort or at-commit cleanup is going to need work to extend its data structures to handle subtransactions. That seems like a major mess :-( regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to majordomo@postgresql.org so that your message can get through to the mailing list cleanly