We have 100's of shapefiles for which we have to generate excel reports based on a few (combination of) parameters in the attribute table. I am using SQL query to achieve this and when I run the query in the "Create Virtual layer" process, it works fine and the output has been generated, which will be saved as an excel file. Instead of this process, I am trying to run this through the Python console. Though the code didn't show any error, the output is not being printed. Do I have to change the SQL query format in the code?

Image 1: For the shapefile final_bdry, Total_Area has to be calculated based on two other columns - MS_Area, Ground_Con (similar to Pivot_Table in excel, the sum of a column based on a unique count of the other two columns). No issues with the query and I am getting the desired output in the virtual_layer. enter image description here.

Image 2: But, if I run the same query within the Python console, the result is "None"

enter image description here

Ref: Used this as ref SQL queries in shapefiles using python/gdal return none result


You could try directly inserting your SQL query when creating a Virtual layer:

query = """ SELECT "MS_Area", "Ground_Con", sum("Area_Ha") as Total /*:ini*/ from final_bdry group by "MS_Area", "Ground_Con" """

vlayer = QgsVectorLayer( "?query={}".format(query), "vlayer", "virtual" )




QgsMapLayerRegistry object was changed in QGIS 3.0 for QgsProject. So, last line in 3.0 should be:


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