opengeodb select

gistfile1.sql

/* select one test zip */
SELECT zc_id, zc_location_name, zc_lat, zc_lon 
FROM zip_coordinates
WHERE zc_zip = '13187';

/* calculate with the found data from above the zip in the radius < 20km */
SELECT 
    zc_zip, 
    zc_location_name,
    ACOS(
         SIN(RADIANS(zc_lat)) * SIN(RADIANS(52.5710506114498)) 
         + COS(RADIANS(zc_lat)) * COS(RADIANS(52.5710506114498)) * COS(RADIANS(zc_lon)
         - RADIANS(13.4049687142945))
         ) * 6380 AS distance
FROM zip_coordinates
WHERE ACOS(
         SIN(RADIANS(zc_lat)) * SIN(RADIANS(52.5710506114498)) 
         + COS(RADIANS(zc_lat)) * COS(RADIANS(52.5710506114498)) * COS(RADIANS(zc_lon)
         - RADIANS(13.4049687142945))
         ) * 6380 < 20
  AND zc_id <> 9739
ORDER BY distance,zc_zip;