MySQL calculates the data within the longitude and latitude range

Using Google solutions

The SQL statement that will find the closest 20 locations that are within a radius of 30 miles to the 78.3232, 65.3234 coordinate. It calculates the distance based on the latitude/longitude of that row and the target latitude/longitude, and then asks for only rows where the distance value is less than 30 miles, orders the whole query by distance, and limits it to 20 results. To search by kilometers instead of miles, replace 3959 with 6371.

Example ：（ Google ）

SELECT
  id, (
    3959 * acos (
      cos ( radians(78.3232) )
      * cos( radians( lat ) )
      * cos( radians( lng ) - radians(65.3234) )
      + sin ( radians(78.3232) )
      * sin( radians( lat ) )
    )
  ) AS distance
FROM markers
HAVING distance < 30
ORDER BY distance
LIMIT 0 , 20;

These are Google instructions , The following is translated by Google

According to the above description , There are the following application examples

among

3959 Is miles of the radius of the earth ,6371 Is the kilometer of the radius of the earth ,LATITUDE Is the longitude of the database field ,LONGITUDE Is the latitude of the database ,18.7777 Is the longitude of the search ,55.3774 Is the latitude of the search, that is （18.7777,55.3774） This position is a little Search the neighborhood 3.7KM The location data of

SELECT
  id, (
    3959 * acos (
      cos ( radians(18.7777) )
      * cos( radians( LATITUDE) )
      * cos( radians( LONGITUDE) - radians(55.3774) )
      + sin ( radians(18.7777) )
      * sin( radians( LATITUDE) )
    )
  ) AS distance
FROM markers
HAVING distance < 3700
ORDER BY distance
LIMIT 0 , 20;