Hi all. Once again, I’m looking into migrating to Cayenne from EOF :). One question though: Our code depends heavily on raw row fetching (data rows) that traverses relationships. I haven’t looked much at the Cayenne code, but do you believe adding support for this to Cayenne would be a huge undertaking? Or does Cayenne perhaps provide an alternative method to achieve the same results?
Cheers, - hugi // Hugi Thordarson // http://www.loftfar.is/ <http://www.loftfar.is/> // s. 895-6688 > On 31. okt. 2014, at 08:50, Andrus Adamchik <[email protected]> wrote: > >> My problem with the solution is just the integration into Cayenne. > > EJBQLQuery supports aggregates: > > http://cayenne.apache.org/docs/3.1/cayenne-guide/queries.html#ejbqlquery > > The problem with it is that the query itself can only be created from String > using a JPQL-like object query language, so you forfeit the type safety of > SelectQuery. Still it is a much better abstraction then SQLTemplate for > instance. (And its integration into SelectQuery is on the agenda). > > Andrus > > >> On Oct 31, 2014, at 1:38 AM, Mark Stobbe <[email protected]> wrote: >> >> @Andrus, I see. Good to know how to do this in Cayenne. >> >> @Michael, You are right. It makes more sense to let the database do the >> calculations. It prevents the race conditions when updating and ensures >> totals to be correct. >> My problem with the solution is just the integration into Cayenne. >> Do you use some extra classes to keep the totals? It would be perfect if the >> expression language could be extended to have an easy way to group and count >> associated entities!! >> >> >>> On 30 okt. 2014, at 18:22, Michael Gentry <[email protected]> wrote: >>> >>> The utilities I mentioned also do SUM, AVG, MIN, and MAX ... >>> >>> >>>> On Thu, Oct 30, 2014 at 12:35 PM, Mark Stobbe <[email protected]> >>>> wrote: >>>> Oh, I also have the same problem with total cost with different >>>> currencies... >>>> >>>>> On Thu, Oct 30, 2014 at 5:09 PM, Mark Stobbe <[email protected]> >>>>> wrote: >>>>> >>>>> Hi Michael, >>>>> >>>>> I would like to display the count in a table for a whole bunch of orders. >>>>> In theory I could use a "group by"-query to get the numbers I need and >>>>> with proper configured indices this should be fairly quick, I guess. >>>>> >>>>> Is there a more transparent way of doing things, e.g. using lifecycle >>>>> listeners, datachannel filters and such? >>>>> >>>>> Mark >>>>> >>>>> On Thu, Oct 30, 2014 at 4:15 PM, Michael Gentry <[email protected]> >>>>> wrote: >>>>> >>>>>> Hi Mark, >>>>>> >>>>>> Is there a performance reason why you don't just do a count on the >>>>>> packages that match the order? >>>>>> >>>>>> mrg >>>>>> >>>>>> >>>>>> On Thu, Oct 30, 2014 at 11:00 AM, Mark Stobbe <[email protected]> >>>>>> wrote: >>>>>>> Hi all, >>>>>>> >>>>>>> I was wondering what is the best way to update totals in a multi-user >>>>>>> environment. For example, let's say we have an Order which can have one >>>>>> or >>>>>>> more Packages associated and we want to maintain a total package count >>>>>> on >>>>>>> the Order entity. How would you update this value when the user has the >>>>>>> option to add/remove packages. >>>>>>> >>>>>>> So the entities looks like: >>>>>>> >>>>>>> *Order* >>>>>>> -------- >>>>>>> id : bigint >>>>>>> orderNumber : varchar >>>>>>> nrOfPackages : int >>>>>>> >>>>>>> *Package* >>>>>>> ------------ >>>>>>> id : bigint >>>>>>> packageNumber : varchar >>>>>>> *fk_order : bigint* >>>>>>> >>>>>>> What do you guys use to solve this? >>>>>>> Mark >>>>> >>>>> >> >
