在下面的查询中,什么是“cos(弧度(lat)”或“cos(弧度(lng)或”弧度(lat)“)?弧度()功能吗?使用sql查询经纬度的半径搜索
SELECT id, (3959 * acos(cos(radians(37))
* cos(radians(lat))
* cos(radians(lng)
- radians(-122)) + sin(radians(37))
* sin(radians(lat)))) AS distance
FROM markers
HAVING distance < 25
ORDER BY distance LIMIT 20 OFFSET 0;
http://dev.mysql.com/doc/refman/5.0/en/mathematical-functions.html#function_radians – Noel