Hmm are you sure we don't do this already? I suspect we do. Each provider can handle the sorting, giving to it by QgsFeatureRequest, and hand the results back to the caller. I thought the attribute table was already implemented this way.
Regards, Nathan On Sat, Mar 4, 2017 at 6:03 PM, Tobias Wendorff < tobias.wendo...@tu-dortmund.de> wrote: > Am Sa, 4.03.2017, 08:34 schrieb Alessandro Pasotti: > > > > Yes, that would be a strategy, but you might run into problem with > > sorting and filtering if the data provider does not support for it. > > All database-like formats, even Shapefile's DBF, support sorting > on database level. I've never understood, why some applications > download the whole content first and > > Microsoft Access is such a "problem". Some days ago, it has downloaded > 700 MB of data from the database to figure out "first" and "min/max". > Access has a "pass-through" function for this to make it directly > work on database level, but it's somehow hard to handle. > > But you're right. For things like sorting in calculation, there > has to be a different solution, like threaded or staged or using > "processing" toolbar only. > > My system can't even handle to download 3 * 10^6 attributes :( > > _______________________________________________ > Qgis-user mailing list > Qgis-user@lists.osgeo.org > List info: https://lists.osgeo.org/mailman/listinfo/qgis-user > Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user >
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