I have 2 layers and I want to make a clip of layer 1 with layer 2 in SpatiaLite (I'm using the DB Manager within QGIS).
That's the code I'm using:
create table clipped_lines as select * from lines, estensione where st_intersects(lines.GEOMETRY, extension.geom)
The table is created but it is not a geographical object so I cannot add it to the QGIS map canvas.
The problem (I think) is that the geom column is seen as a normal column and not as a GEOMETRY column. I've tried to update the column with:
ALTER TABLE clipped_lines ALTER COLUMN geom TYPE GEOMETRY(LineString,4326);
but nothing happened.
I thought that the
st_intersects function updates automatically the geom column.