我有经纬度,我想从数据库中提取记录,它有最近的经纬度,如果这个距离比指定的长,就不检索它。

表结构:

id
latitude
longitude
place name
city
country
state
zip
sealevel

当前回答

在极端情况下,这种方法会失败,但为了性能考虑,我跳过了三角函数,只是简单地计算对角线的平方。

其他回答

查找离我最近的用户:

距离(米)

根据文森特提的公式

i有用户表:

+----+-----------------------+---------+--------------+---------------+
| id | email                 | name    | location_lat | location_long |
+----+-----------------------+---------+--------------+---------------+
| 13 | xxxxxx@xxxxxxxxxx.com | Isaac   | 17.2675625   | -97.6802361   |
| 14 | xxxx@xxxxxxx.com.mx   | Monse   | 19.392702    | -99.172596    |
+----+-----------------------+---------+--------------+---------------+

sql:

-- my location:  lat   19.391124   -99.165660
SELECT 
(ATAN(
    SQRT(
        POW(COS(RADIANS(users.location_lat)) * SIN(RADIANS(users.location_long) - RADIANS(-99.165660)), 2) +
        POW(COS(RADIANS(19.391124)) * SIN(RADIANS(users.location_lat)) - 
       SIN(RADIANS(19.391124)) * cos(RADIANS(users.location_lat)) * cos(RADIANS(users.location_long) - RADIANS(-99.165660)), 2)
    )
    ,
    SIN(RADIANS(19.391124)) * 
    SIN(RADIANS(users.location_lat)) + 
    COS(RADIANS(19.391124)) * 
    COS(RADIANS(users.location_lat)) * 
    COS(RADIANS(users.location_long) - RADIANS(-99.165660))
 ) * 6371000) as distance,
users.id
FROM users
ORDER BY distance ASC

地球半径:6371000(单位:米)

MS SQL版本在这里:

        DECLARE @SLAT AS FLOAT
        DECLARE @SLON AS FLOAT

        SET @SLAT = 38.150785
        SET @SLON = 27.360249

        SELECT TOP 10 [LATITUDE], [LONGITUDE], SQRT(
            POWER(69.1 * ([LATITUDE] - @SLAT), 2) +
            POWER(69.1 * (@SLON - [LONGITUDE]) * COS([LATITUDE] / 57.3), 2)) AS distance
        FROM [TABLE] ORDER BY 3
simpledb.execSQL("CREATE TABLE IF NOT EXISTS " + tablename + "(id INTEGER PRIMARY KEY   AUTOINCREMENT,lat double,lng double,address varchar)");
            simpledb.execSQL("insert into '" + tablename + "'(lat,lng,address)values('22.2891001','70.780154','craftbox');");
            simpledb.execSQL("insert into '" + tablename + "'(lat,lng,address)values('22.2901396','70.7782428','kotecha');");//22.2904718 //70.7783906
            simpledb.execSQL("insert into '" + tablename + "'(lat,lng,address)values('22.2863155','70.772108','kkv Hall');");
            simpledb.execSQL("insert into '" + tablename + "'(lat,lng,address)values('22.275993','70.778076','nana mava');");
            simpledb.execSQL("insert into '" + tablename + "'(lat,lng,address)values('22.2667148','70.7609386','Govani boys hostal');");


    double curentlat=22.2667258;  //22.2677258
    double curentlong=70.76096826;//70.76096826

    double curentlat1=curentlat+0.0010000;
    double curentlat2=curentlat-0.0010000;

    double curentlong1=curentlong+0.0010000;
    double curentlong2=curentlong-0.0010000;

    try{

        Cursor c=simpledb.rawQuery("select * from '"+tablename+"' where (lat BETWEEN '"+curentlat2+"' and '"+curentlat1+"') or (lng BETWEEN         '"+curentlong2+"' and '"+curentlong1+"')",null);

        Log.d("SQL ", c.toString());
        if(c.getCount()>0)
        {
            while (c.moveToNext())
            {
                double d=c.getDouble(1);
                double d1=c.getDouble(2);

            }
        }
    }
    catch (Exception e)
    {
        e.printStackTrace();
    }

这个问题最初的答案是好的,但是mysql的新版本(mysql 5.7.6上)支持地理查询,所以你现在可以使用内置的功能,而不是进行复杂的查询。

你现在可以这样做:

select *, ST_Distance_Sphere( point ('input_longitude', 'input_latitude'), 
                              point(longitude, latitude)) * .000621371192 
          as `distance_in_miles` 
  from `TableName`
having `distance_in_miles` <= 'input_max_distance'
 order by `distance_in_miles` asc

结果以米为单位返回。因此,如果你想计算KM,只需使用。001而不是。000621371192(这是英里)。

MySql文档在这里

以防你像我一样懒,这里有一个解决方案,由这个和其他关于SO的答案合并而成。

set @orig_lat=37.46; 
set @orig_long=-122.25; 
set @bounding_distance=1;

SELECT
*
,((ACOS(SIN(@orig_lat * PI() / 180) * SIN(`lat` * PI() / 180) + COS(@orig_lat * PI() / 180) * COS(`lat` * PI() / 180) * COS((@orig_long - `long`) * PI() / 180)) * 180 / PI()) * 60 * 1.1515) AS `distance` 
FROM `cities` 
WHERE
(
  `lat` BETWEEN (@orig_lat - @bounding_distance) AND (@orig_lat + @bounding_distance)
  AND `long` BETWEEN (@orig_long - @bounding_distance) AND (@orig_long + @bounding_distance)
)
ORDER BY `distance` ASC
limit 25;