On Fri, Mar 25, 2005 at 06:46:58PM -0500, Tom Lane wrote: > Also, you just introduced a race condition, since the transaction might > have committed after the earlier tests and before you did > TransactionIdIsInProgress. You really have to do > TransactionIdIsInProgress *first*, which makes the proposed change even > more expensive.
Oh, right. I knew there was a reason, I just couldn't remember it. > What's wrong with using XactLockTableWait? It's not going away --- the > implementation might change but I can't see getting rid of the > functionality. Nothing wrong indeed, if you take this PoV. That's exactly what I've done now, since it is what heap_mark4update (which I'm replacing) does at present. (I use LockTuple(), a lock which is only released at transaction end, so the net result is semantically equivalent to XactLockTableWait -- that's why I want to get rid of it.) -- Alvaro Herrera (<[EMAIL PROTECTED]>) "El sentido de las cosas no viene de las cosas, sino de las inteligencias que las aplican a sus problemas diarios en busca del progreso." (Ernesto Hernández-Novich) ---------------------------(end of broadcast)--------------------------- TIP 2: you can get off all lists at once with the unregister command (send "unregister YourEmailAddressHere" to [EMAIL PROTECTED])