百度地图中,如何根据一个坐标点搜索数据库中附近多少距内的N个坐标点
环境:php+mysql
现有数据库中存放一些经纬度(100W以上)坐标点,
如果根据一个坐标点获取附近1公里内的所有符合信息?
数据库中 经度字段lng 纬度字段lat。。
使用的是百度地图。
在线等 谢谢。
------解决方案--------------------
排序坐标列
筛选欧几里得距离符合条件的记录
------解决方案--------------------
我认为这样:
既然有了中心点经纬度,那么可以根据维度,计算出符合N公里的经纬度大致范围。。这样搜出的结果是个2N*2N的正方形,
比如北纬34.5°,1公里就没必要找北纬35+或者34-的点,具体的可以先程序中换算
不过尚需过滤一部分,圆半径N之外的部分,
如果这样可以,只要lng lat联合索引,百万规模,非常快速

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