select within 20 kilometers based on latitude/longitude

Question

i have a mysql table structured as per the example below:

POSTAL_CODE_ID|PostalCode|City|Province|ProvinceCode|CityType|Latitude|Longitude
7|A0N 2J0|Ramea|Ne         


        

Answer 1

SELECT `s`.suburb_id,`s`.suburb_name,`s`.lat,`s`.long, (((acos(sin(($lat*pi()/180)) * sin((s.lat*pi()/180))+cos(($lat*pi()/180)) * cos((s.lat*pi()/180)) * cos((($long - s.long)*pi()/180))))*180/pi())*60*1.1515*1.609344) AS distance FROM (`mst_suburbs` as s) HAVING distance <= 20 ORDER BY `s`.suburb_id DESC

This query works for me to get all the lat,long between 12 km distance.I have mst_suburbs is may table which having the lat and long column.$lat and $long are my two php variable .and I am passing the desired lat,long to get the nearest 12km lat long list from the mst_suburb. You just need to change the name of the column according to your table and pass the lat,long to query.

Answer 2

You simply take your haversine formula and apply it like this:

SELECT   *,
         6371 * ACOS(SIN(RADIANS( $lat1 )) * SIN(RADIANS(`Latitude`)) +
         COS(RADIANS( $lat1 )) * COS(RADIANS(`Latitude`)) * COS(RADIANS(`Longitude`) -
         RADIANS( $lon1 ))) AS `distance`
FROM     `table`
WHERE    `distance` <= 20
ORDER BY `distance` ASC

Replace $lat1 and $lon1 with the latitude and longitude you want to compare against.

Answer 3

It's a little complicated algorithm, but here's a link to one solution

Answer 4

SELECT  *
FROM    mytable m
JOIN    mytable mn
ON      ACOS(COS(RADIANS(m.latitude)) * COS(RADIANS(mn.latitude)) * COS(RADIANS(mn.longitude) - RADIANS(m.longitude)) + SIN(RADIANS(m.latitude)) * SIN(radians(mn.latitude))) <= 20 / 6371.0
WHERE   m.name = 'grey river'

If your table is MyISAM you may want to store your points in a native geometry format and create a SPATIAL index on it:

ALTER TABLE mytable ADD position POINT;

UPDATE  mytable
SET     position = POINT(latitude, longitude);

ALTER TABLE mytable MODIFY position NOT NULL;

CREATE SPATIAL INDEX sx_mytable_position ON mytable (position);

SELECT  *
FROM    mytable m
JOIN    mytable mn
ON      MBRContains
                (
                LineString
                        (
                        Point
                                (
                                X(m.position) - 0.009 * 20,
                                Y(m.position) - 0.009 * 20 / COS(RADIANS(X(m.position)))
                                ),
                        Point
                                (
                                X(m.position) + 0.009 * 20,
                                Y(m.position) + 0.009 * 20 / COS(RADIANS(X(m.position))
                                )
                        ),
                mn.position
                )
        AND ACOS(COS(RADIANS(m.latitude)) * COS(RADIANS(mn.latitude)) * COS(RADIANS(mn.longitude) - RADIANS(m.longitude)) + SIN(RADIANS(m.latitude)) * SIN(radians(mn.latitude))) <= 20 / 6371.0
WHERE   m.name = 'grey river'