> I've been filtering a layer by adding a virtual column populated with > is_selected() and then creating a virtual layer from it using the > filter: WHERE virtualField = 1 > > This is working well and allows you to have a copy of the layer that > only shows the selected records when you are creating a layout.
What's your use case for this? I just wonder whether there is an alternative that might be easier? For example if you're always selecting the same set of features, you could add a category/classification column and then filter based on that. > I now need to bring in an associated layer, but I can't find a > reliable way to cross layer filter because QGIS just hangs for ages > and crashes. I have found that QGIS can be extremely slow sometimes when joining tables and can often crash, so if there's a solution that can avoid this you might find it more robust. > I've searched around and can see a lot of people talk about making > the database do the work but of course it can't if you are trying to > use a selection filter. So there's definitely no way you can classify your data such that you don't need to use a selection filter? > What is the most reliable way of setting up a filter based on a join > because QGIS tells me that I must use a virtual layer and even > creates it for me; but then it just hangs and crashes. I suppose you could export the virtual selection layer (or even forget the layer and just use "export selected features") and put those in a real database table, which you then link off instead? It would be a more laborious process having to do an export each time you wish to select different features but it might at least allow the workflow to complete. Cheers, Adam. _______________________________________________ QGIS-User mailing list [email protected] List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
