Re: autonomous transactions

2016-10-11 21:54 GMT+02:00 Merlin Moncure <mmoncure(at)gmail(dot)com>:

> On Tue, Oct 11, 2016 at 10:06 AM, Petr Jelinek <petr(at)2ndquadrant(dot)com>
> wrote:
> > On 10/10/16 16:44, Merlin Moncure wrote:
> >> On Thu, Oct 6, 2016 at 3:53 PM, Simon Riggs <simon(at)2ndquadrant(dot)com>
> wrote:
> >>> On 6 October 2016 at 21:27, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> >>>> I think we should implement background transactions and call them
> >>>> background transactions. That allows us to expose additional
> >>>> functionality which is useful, like the ability to kick something off
> >>>> and check back later for the results. There's no reason to call it
> >>>> background transactions and also call it autonomous transactions: one
> >>>> feature doesn't need two names.
> >>>
> >>> I'm happy to also invoke it via an alternate mechanism or API, so that
> >>> it can continue to be used even if the above mechanism changes.
> >>>
> >>> We have no need to wait for the perfect solution, even assuming we
> >>> would ever agree that just one exists.
> >>
> >> -1 on implementing both autonomous and background transactions. This
> >> will confuse everyone.
> >
> > I personally care much more about having background transactions than
> > autonomous ones (as I only ever had use-cases for the background ones)
> > so don't agree there.
>
> All right. But would you agree then that AT should at least emulate
> competing implementations? A major advantage of bgworkers is possibly
> supporting concurrent activity and maybe the syntax could be more
> directed to possibly moving in that direction other than copying
> oracle style (PRAGMA etc), particularly if the locking rules are
> substantially different.
>

There is a big trap - AT is usually used for writing to log tables. When BT
fails on maximum active workers then, then you cannot do any expected
operation.

Regards

Pavel

>
> merlin
>
>
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