Find points (a.k.a users) within a distance using MySQL

Magic SQL Statement

# :lat as your requested latitude
# :lon as your requested longitude
# :r as your Earth's radius - Could be 6371 for KM or 3959 for miles
# :rad as your radius search distance

SELECT
 `userId`,
 `name`,
 `address`,
 AsText(`spatialData`) AS 'spatialData',
 acos(sin(:lat) * sin(radians(X(`spatialData`))) + cos(:lat)*cos(radians(X(`spatialData`)))*cos(radians(Y(`espacial`))-:lon))*:r AS 'Distance',
 X(`spatialData`) AS 'lat',
 Y(`spatialData`) AS 'lon'
FROM
`users`
WHERE
Distance <= :rad
ORDER BY Distance