On Fri, Oct 13, 2023 at 4:18 AM Robert Haas <robertmh...@gmail.com> wrote: > On Thu, Oct 12, 2023 at 6:54 PM Alexander Korotkov <aekorot...@gmail.com> > wrote: > > On Thu, Oct 12, 2023 at 8:35 PM Robert Haas <robertmh...@gmail.com> wrote: > > > > Doesn't that mean that if you create the first login trigger in a > > > database and leave the transaction open, nobody can connect to that > > > database until the transaction ends? > > > > It doesn't mean that, because when trying to reset the flag v44 does > > conditional lock. So, if another transaction is holding the log we > > will just skip resetting the flag. So, the flag will be cleared on > > the first connection after that transaction ends. > > But in the scenario I am describing the flag is being set, not reset.
Sorry, it seems I just missed some logical steps. Imagine, that transaction A created the first login trigger and hangs open. Then the new connection B sees no visible triggers yet, but dathasloginevt flag is set. Therefore, connection B tries conditional lock but just gives up because the lock is held by transaction A. Also, note that the lock has been just some lock with a custom tag. It doesn't effectively block the database. You may think about it as of custom advisory lock. ------ Regards, Alexander Korotkov
