SQLite can be built with the R*tree module, which supports efficiently looking up all bounding boxes that contain a point: https://www.sqlite.org/rtree.html
PostGIS similarly provides an R*Tree index mode, as well as a heap of functions for doing GIS calculations directly. To do that in SQLite, you'd implement and inject custom functions as appropriate.
PostGIS similarly provides an R*Tree index mode, as well as a heap of functions for doing GIS calculations directly. To do that in SQLite, you'd implement and inject custom functions as appropriate.