Near Latitide&Longitide; for given postcode

[eluser]veledrom[/eluser]
This is in KMs.

Code:

SELECT
     postcode,
     (((ACOS(sin(('51.546069024064' * PI() / 180)) * SIN((latitude * PI() / 180)) +
     COS(('51.546069024064' * PI() / 180)) * COS((latitude * PI() / 180)) *
     COS((('-0.235949008191785' - longitude) * PI() / 180)))) * 180 / PI()) * 60 * 1.1515 * 1.609344) AS Distance
    FROM postcodes
    HAVING Distance <= '1'
    ORDER BY Distance ASC