MySQL calculates the nearest store

Incoming parameters latitude 40.0497810000 longitude 116.3424590000/*The parameter passed in is latitude latitude longitude asc ascending from near to far desc descending from far to near*/SELECT*,ROUND(        6378.138 * 2 *ASIN(            SQRT(                POW(                    SIN(                        (                            40.0497810000 *PI()/180-lat *PI()/180                        ) /2                    ), 2                ) +COS(40.0497810000 *PI()/180) *COS(LAT *PI()/180) *POW(                    SIN(                        (                            116.3424590000 *PI()/180-lon *PI()/180                        ) /2                    ), 2                )            )        ) * 1000    )  asJulifrom CustomerOrder by Juli ASC

This will calculate all the stores in the database once, and in the actual use, it is unlikely that the need to calculate the user's distance from all other users, and then sort the situation, when the number of users reached a level, you can search in a smaller scope, rather than all users.

So for this example, I've added 4 where conditions, only for distance calculations for users with longitude and latitude greater than or less than 1 degrees (111 km) of the user, and an index to the longitude and latitude two columns in the data table to optimize the speed at which the where statement executes.

The final SQL statement is as follows

$sql=SELECT * from users_location where latitude >‘.$lat.‘-1 and Latitude <‘.$lat.‘+1 and Longitude >‘.$lon.‘-1 and longitude <‘.$lon.‘+1 ORDER by ACOS (SIN (‘.$lat. ' * 3.1415)/*sin ((Latitude * 3.1415)/+cos ('.$lat) * COS ((latitude * 3.1415)/3.1415) *cos (('.$lon.‘ * 3.1415)/Longitude-(* 3.1415)/+) * 6380 ASC limit 10 '; 

MySQL calculates the nearest store