Hi Hugi, >From what I've read, UUID PKs have poor index performance and take up more storage.
Wouldn't it be better to use an integer sequence like PostgreSQL and Oracle support? You can generate your PKs up front and Cayenne already knows how to deal with them. Thanks, mrg On Thu, Aug 15, 2024 at 6:49 AM Hugi Thordarson <h...@godurkodi.is> wrote: > Hi Nikita, > > again, thanks for looking into this! And yeah, totally understand how > we're not about to insert everything in one commit. Well, at least until > the universe decides it's time everyone move to app generated UUID PKs and > deferred constraint checks :). > > Cheers, > - hugi > > > > > On 14 Aug 2024, at 11:27, Nikita Timofeev <ntimof...@objectstyle.com> > wrote: > > > > In this case it seems like a true cycle, the Person entity has two > > relationships to self. And that particular case Cayenne didn't handle > well > > historically. > > But looking at it, I want to try and tweak the new Graph-based sorter, > > because two updates generated shouldn't depend on each other. So maybe it > > could be fixed now. > > It still won't be able to insert all the data in one go though. > > > > On Wed, Aug 14, 2024 at 11:33 AM Hugi Thordarson <h...@godurkodi.is> > wrote: > > > >> Hi again Nikita! > >> > >> saw the fix you made yesterday and it works great for the test I > created, > >> so thanks for that! > >> > >> However, turns out that for the more complex case in our actual project, > >> the operation still fails. > >> I've added a new example to the test project that models that case a > >> little more closely: > >> > >> > >> > https://github.com/hugithordarson/xx-c42/blob/main/src/main/java/family/MainWithAddedBackReference.java > >> > >> Any thoughts? > >> > >> Cheers, > >> - hugi > >> > >> > >> > >>> On 12 Aug 2024, at 13:52, Nikita Timofeev <ntimof...@objectstyle.com> > >> wrote: > >>> > >>> Hi Hugi, > >>> > >>> Thanks for the perfect example, that's always my main problem. > >>> I've found the issue with the new flush logic [1]. The last operation > >>> creates two logical changes (DbRowOps), and one of them is later > >> discarded > >>> as there's nothing to flush to the DB. > >>> However it's discarded only after the sorting, so it fails. > >>> I'm already testing a fix for that. > >>> > >>> Also wanted to mention that in this exact case GraphBasedDbRowOpSorter > >>> helps, as it checks operation internals and ignores it. > >>> > >>> [1] https://issues.apache.org/jira/browse/CAY-2866 > >>> > >>> On Fri, Aug 9, 2024 at 12:58 PM Hugi Thordarson <h...@godurkodi.is> > >> wrote: > >>> > >>>> Hi Andrus, > >>>> I've been taking a look at this with Maik, here's a runnable example > >>>> project containing a commit that works on v4.1 but fails in v4.2: > >>>> > >>>> https://github.com/hugithordarson/xx-c42/ > >>>> > >>>> Quick link to the code actually demonstrating the failure: > >>>> > >>>> > >> > https://github.com/hugithordarson/xx-c42/blob/main/src/main/java/family/Main.java > >>>> > >>>> The last commit certainly results in a circular reference being > present > >> in > >>>> the object graph, but it probably shouldn't be a problem for the > actual > >>>> operation since we're only updating a single row, right? > >>>> > >>>> Cheers, > >>>> - hugi > >>>> > >>>> > >>>> > >>>> > >>>> > >>>> > >>>>> On 8 Aug 2024, at 18:10, Andrus Adamchik <aadamc...@gmail.com> > wrote: > >>>>> > >>>>> Hi Maik, > >>>>> > >>>>> Could you provide an example of a failing graph? > >>>>> > >>>>> Thanks, > >>>>> Andrus > >>>>> > >>>>>> On Aug 7, 2024, at 7:31 AM, Maik Musall <m...@selbstdenker.ag> > wrote: > >>>>>> > >>>>>> Hi everyone, > >>>>>> > >>>>>> we upgraded an application from Cayenne 4.1.1 to 4.2.1, and now > we’re > >>>> getting more cyclic graph errors from AshwoodEntitySorter. Years back > we > >>>> already had a similar problem, but @SortWeight didn’t help and > >>>> GraphBasedDbRowOpSorter wasn’t ready. The latter is now in 4.2 stable > >> but > >>>> fails to save even simpler graphs, so unfortunately not a solution. We > >> had > >>>> been able to get stable operation by fetching PK’s from PostgreSQL > >>>> sequences (Oracle-style) instead of having Cayenne generate them, and > >> lived > >>>> with the performance penalty associated with that, but the problem > came > >>>> back with 4.2 despite that. Not reliably reproducible though, happens > >> every > >>>> now and then. Any thoughts? > >>>>>> > >>>>>> Thanks > >>>>>> Maik > >>>>>> > >>>>> > >>>> > >>>> > >>> > >>> -- > >>> Best regards, > >>> Nikita Timofeev > >> > >> > > > > -- > > Best regards, > > Nikita Timofeev > >
