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Home Backend Development PHP Tutorial 百度map中,怎么根據(jù)一個(gè)坐標(biāo)點(diǎn)搜索數(shù)據(jù)庫(kù)中附近多少距內(nèi)的N個(gè)坐標(biāo)點(diǎn)

百度map中,怎么根據(jù)一個(gè)坐標(biāo)點(diǎn)搜索數(shù)據(jù)庫(kù)中附近多少距內(nèi)的N個(gè)坐標(biāo)點(diǎn)

Jun 13, 2016 pm 12:02 PM
100W mysql nbsp

百度地圖中,如何根據(jù)一個(gè)坐標(biāo)點(diǎn)搜索數(shù)據(jù)庫(kù)中附近多少距內(nèi)的N個(gè)坐標(biāo)點(diǎn)
環(huán)境:php+mysql

現(xiàn)有數(shù)據(jù)庫(kù)中存放一些經(jīng)緯度(100W以上)坐標(biāo)點(diǎn),

如果根據(jù)一個(gè)坐標(biāo)點(diǎn)獲取附近1公里內(nèi)的所有符合信息?

數(shù)據(jù)庫(kù)中?經(jīng)度字段lng?緯度字段lat。。

使用的是百度地圖。

在線等?謝謝。

------解決方案--------------------
排序坐標(biāo)列
篩選歐幾里得距離符合條件的記錄
------解決方案--------------------
我認(rèn)為這樣:

既然有了中心點(diǎn)經(jīng)緯度,那么可以根據(jù)維度,計(jì)算出符合N公里的經(jīng)緯度大致范圍。。這樣搜出的結(jié)果是個(gè)2N*2N的正方形,

比如北緯34.5°,1公里就沒必要找北緯35+或者34-的點(diǎn),具體的可以先程序中換算

不過尚需過濾一部分,圓半徑N之外的部分,

如果這樣可以,只要lng?lat聯(lián)合索引,百萬(wàn)規(guī)模,非??焖?/p>

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