----- Original Message ----- > From: "Moti Asayag" <masa...@redhat.com> > To: "Eli Mesika" <emes...@redhat.com> > Cc: "engine-de...@ovirt.org" <devel@ovirt.org> > Sent: Wednesday, March 11, 2015 11:53:50 AM > Subject: Re: [ovirt-devel] Important changes in the Search Engine code > > > > ----- Original Message ----- > > From: "Eli Mesika" <emes...@redhat.com> > > To: "engine-de...@ovirt.org" <devel@ovirt.org> > > Sent: Wednesday, March 11, 2015 10:48:44 AM > > Subject: [ovirt-devel] Important changes in the Search Engine code > > > > Hi All > > > > We had in the past many cases in which the search engine returned duplicate > > records. > > Most of those cases are not simple to resolve in the DB layer by changing > > the > > query due to schema limitations. > > We had decided to handle that by adding DISTINCT to the queries that the > > search engine generates [1] > > Wouldn't that cause some penalty for each query ? Each navigation between > tabs in > the UI will become slower now that the returned values need to be sorted, > even when > not required ?
We had tested that for a while and the penalty is relatively small. We surely can come with a better solution but it requires heavy schema changes I think we can live with that .... > > > However, we might have cases in which both DISTINCT and ORDER BY f({args}) > > (where f is a function call) is used > > In that case, we will get SQL exception since the ORDER BY is applied on > > the > > DISTINCT result that does not include f as a field. > > I had prevented using DISTINCT in such cases [2] > > That means that you still may got duplicates in such cases and then you > > should handle it in the same method as in [3] > > (basically returning the function result in the select as a computed field) > > > > > > [1] https://gerrit.ovirt.org/#/c/31896 > > [2] https://gerrit.ovirt.org/#/c/38459 > > [3] https://gerrit.ovirt.org/#/c/36946 > > > > > > Thanks > > Eli Mesika > > > > _______________________________________________ > > Devel mailing list > > Devel@ovirt.org > > http://lists.ovirt.org/mailman/listinfo/devel > > > _______________________________________________ Devel mailing list Devel@ovirt.org http://lists.ovirt.org/mailman/listinfo/devel