"Simon Riggs" <[EMAIL PROTECTED]> writes: > Sounds good. The cost is paid by the WHERE CURRENT OF query, not as an > overhead on all cursors. Sounds like it will still be very fast too.
Yeah, there's zero added cost in the existing code paths, and the lookup isn't really that expensive. > Presumably still disallowing the WITH HOLD case. Right --- once you've committed, you can't be sure the rows are still there to look at. I just finished revising the patch and am about to commit it. In the event, my idea of a separate lookup function didn't work so well --- it needed to be STABLE to be used in a tidscan qual, but it also needed to be VOLATILE to prevent the planner from speculatively executing it (resulting in premature failure if the cursor wasn't there at plan time). So I ended up letting the special CurrentOfExpr node type persist all the way through to execution. This required very minor hackery in tidpath.c and nodeTidscan.c to accept such a node as a TID qual; it would've taken something uglier to make the function representation work. One area that could still do with more work is getting the facility to play nicely with views. However, it's probably premature to think about that before we have updatable views that work well... regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly