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Examples of mysql searching for data within N kilometers nearby

jacklove

Jun 08, 2018 pm 11:16 PM

locationmysql

Based on the pi ratio, the earth's radius coefficient and the longitude and latitude of the search point, search for data within N kilometers of the search point in the data table.

1.Create test table

CREATE TABLE `location` ( `id` int(10) unsigned NOT NULL AUTO_INCREMENT, `name` varchar(50) NOT NULL, `longitude` decimal(13,10) NOT NULL, `latitude` decimal(13,10) NOT NULL, PRIMARY KEY (`id`), KEY `long_lat_index` (`longitude`,`latitude`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

2.Insert test data

insert into location(name,longitude,latitude) values
(&#39;广州东站&#39;,113.332264,23.156206),
(&#39;林和西&#39;,113.330611,23.147234),
(&#39;天平架&#39;,113.328095,23.165376);mysql> select * from `location`;
+----+--------------+----------------+---------------+| id | name         | longitude      | latitude      |
+----+--------------+----------------+---------------+|  1 | 广州东站      | 113.3322640000 | 23.1562060000 |
|  2 | 林和西        | 113.3306110000 | 23.1472340000 ||  3 | 天平架        | 113.3280950000 | 23.1653760000 |
+----+--------------+----------------+---------------+

3.Search for data within 1 km

Search point coordinates: Times Square 113.323568, 23.146436

6370.996Kilometer is the radius of the earth

Formula for calculating the coordinate distance between two points on the sphere

C = sin(MLatA)sin(MLatB)cos(MLonA-MLonB) cos(MLatA)cos(MLatB)
Distance = RArccos(C)*Pi180

According to the calculation formula, the query statement is as follows:

select * from `location` where (
acos(sin(([#latitude#]*3.1415)/180) * sin((latitude*3.1415)/180) + cos(([#latitude#]*3.1415)/180) * cos((latitude*3.1415)/180) * cos(([#longitude#]*3.1415)/180 - (longitude*3.1415)/180))*6370.996)<=1;

Execute the query:

mysql> select * from `location` where (    -> acos(    -> sin((23.146436*3.1415)/180) * sin((latitude*3.1415)/180) +     -> cos((23.146436*3.1415)/180) * cos((latitude*3.1415)/180) * cos((113.323568*3.1415)/180 - (longitude*3.1415)/180)    -> )*6370.996    -> )<=1;
+----+-----------+----------------+---------------+| id | name      | longitude      | latitude      |
+----+-----------+----------------+---------------+|  2 | 林和西     | 113.3306110000 | 23.1472340000 |
+----+-----------+----------------+---------------+

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