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postgresqlpostgisoverlaparea

how to calculate the overlap area - postgis, postgres?

how to calculate the overlap area?

select ST_Area(ST_Overlaps(geometrya, geometryb)::geometry) from table_name;

Error Message cannot cast type boolean to geometry

Solution

  • ST_OVERLAPS returns a boolean indicating if the geometries do or not overlap each other. To get the geometry of the intersection you can use ST_INTERSECTION

    select ST_Area(ST_INTERSECTION(geometrya, geometryb)) from table_name
 WHERE ST_Overlaps(geometrya, geometryb);