Re: [rules-dev] persistence and optimistic locking

All that should be required is to define a version or timestamp property for the entity in question. Hbn will constrain against that field when it performs the update. If the db returns 0 updated rows, then Hbn will throw the stale exception.

I recall there's a way to pessimistically lock using db locks (select for update, etc.), but I assume that's only valid for the duration of your transaction. I never had call to use it. If you use timestamps, make sure your db columns have millisecond resolution. On Nov 12, 2009, at 10:18 PM, Mark Proctor <mproctor(a)codehaus.org <mailto:mproctor@codehaus.org>> wrote: > Michael Neale wrote: >> I am not aware of peasimistic locking use being very common. When >> people want it, it's generally cause the GUI suggests it (eg bob wants >> to view a file, but Alice has it locked) >> >> > With optimistic locking we can just submit our update and it fails if > something else updted the recorded in the mean time - doing a counter > comparison. With pessemistic we have to download the record first, > compare them, and then upload. As what we are comparing in a binary > blob, we want to avoid pulling that from the db. > > Mark >> Sent from my phone. >> >> On 13/11/2009, at 10:27 AM, Salaboy <salaboy(a)gmail.com <mailto:salaboy@gmail.com>> wrote: >> >> >>> I suppose that the versión field its being used. So, the default must >>> be optimistic >>> >>> - Ing. Mauricio Salatino - >>> >>> On Nov 12, 2009, at 9:43 PM, Michael Neale <michael.neale(a)gmail.com <mailto:michael.neale@gmail.com>> >>> wrote: >>> >>> >>>> I thought optimistic locking was the default ? Or do you mean you >>>> know >>>> how to switch, just that it doesn't work? >>>> >>>> >>>> Sent from my phone. >>>> >>>> On 13/11/2009, at 8:16 AM, Salaboy <salaboy(a)gmail.com <mailto:salaboy@gmail.com>> wrote: >>>> >>>> >>>>> I Will take a look on that >>>>> Sent from my iPhone >>>>> >>>>> On Nov 12, 2009, at 7:33 PM, Mark Proctor <mproctor(a)codehaus.org <mailto:mproctor@codehaus.org>> >>>>> wrote: >>>>> >>>>> >>>>>> Any hibernate guru's out there? Currently the persistence stuff >>>>>> uses >>>>>> pessematic locking, which is slow, in theory we should be using >>>>>> optimistic locking, but I couldn't get it to work. Anyone want to >>>>>> give >>>>>> that a go? >>>>>> >>>>>> Mark >>>>>> >>>>>> _______________________________________________ >>>>>> rules-dev mailing list >>>>>> rules-dev(a)lists.jboss.org <mailto:rules-dev@lists.jboss.org> >>>>>> https://lists.jboss.org/mailman/listinfo/rules-dev >>>>>> >>>>> _______________________________________________ >>>>> rules-dev mailing list >>>>> rules-dev(a)lists.jboss.org <mailto:rules-dev@lists.jboss.org> >>>>> https://lists.jboss.org/mailman/listinfo/rules-dev >>>>> >>>> _______________________________________________ >>>> rules-dev mailing list >>>> rules-dev(a)lists.jboss.org <mailto:rules-dev@lists.jboss.org> >>>> https://lists.jboss.org/mailman/listinfo/rules-dev >>>> >>> _______________________________________________ >>> rules-dev mailing list >>> rules-dev(a)lists.jboss.org <mailto:rules-dev@lists.jboss.org> >>> https://lists.jboss.org/mailman/listinfo/rules-dev >>> >> _______________________________________________ >> rules-dev mailing list >> rules-dev(a)lists.jboss.org <mailto:rules-dev@lists.jboss.org> >> https://lists.jboss.org/mailman/listinfo/rules-dev >> > > _______________________________________________ > rules-dev mailing list > rules-dev(a)lists.jboss.org <mailto:rules-dev@lists.jboss.org> > https://lists.jboss.org/mailman/listinfo/rules-dev ------------------------------------------------------------------------ _______________________________________________ rules-dev mailing list rules-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev