select g.* from(select Gunion(geometry) as geom from MYPLGN) as u, grid as g where area(intersection(g.geometry, u.geom)) = area(g.geometry)
5 Dec 2014
QspatiaLite Use Case: Get Subselection of Grid which Covers Polygon
Here's another short SQL-query which I used to get a subselect from a rectengular grid. Aim is to keep only the grid-cells that fully cover the area of a second polygon-layer - cells which do not overlap the polygon's area completely will be skipped from the new grid-layer.