I have a vector file "data.shp" containing the following fields:
ID, value1, AREA
I want to add a new column "value2" and set it as value1/AREA. Since I want to do that for many columns and files I want to use SQL.
I tried with virtual layer in QGIS with no success. I wrote in the query the following :
ALTER TABLE data ADD value2 float; UPDATE data SET value2 = value1/AREA
Are alter and update commands working with virtual layer? Is there any other way?