Page Comparison

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Of note is the SQL used in the DATA statement which creates a row per ward with a point within each ward polygon which will be used for the lookup. The PostGIS function ST_PointOnSurface returns a POINT guaranteed to lie on the surface of a polygon.

        SELECT
            ogc_fid,
            code,
            name,
            ST_PointOnSurface(wkb_geometry) AS wkb_geometry
        FROM boundaryline.wards_surrey

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