If I use "Join attributes by location" from the menu it works fine but if I'm using it within the Processing modeler it's not working.
I want to sum up previously selected records having a field area (calculated by "Export/add geometry columns").
Surprisingly, the sum fields are created but all records contain NULL.
Did I miss something? Any well known bug which I haven't found with Google? Do these two algorithm works differently?
BTW: If I run "Join attributes by location" from the processing toolbox, the algorithm works fine too.
(I'm using QGIS 2.8.1-Wien.)
Best Answer
Seems to work fine here using QGIS 2.8.2 and Processing 2.9.3.
Both in a model and directly from the toolbox, join by location computes the same sums. The layers have to be in the same CRS, otherwise Processing displays a warning and the intersections will be empty.
The project CRS does not seem to influence the results which is the correct behavior.