用Sql地理不正確的數字

Question

我正在將geoFences轉換成Sql地理實例。目前的問題是針對某些情況。地理數字很奇怪和不準確。

第一個（綠色區域）是一個有效的地理圍欄，第二個是在sql中創建的。

的座標是： -

朗緯度

51.576004 24.125605， 51.580467 24.122041， 51.585875 24.119730， 51.591239 24.118751， 51.597633 24.120043， 51.603470 24.123843， 51.607161 24.126114， 51.609950 24.126976， 51.616087 24.127133， 51.625915 24.125997， 51.639776 24.119691， 51.576004 24.125605

隨着偏差即100米緩衝液。

的SQL代碼： -

geography::STGeomFromText('POLYGON((51.576004 24.125605, 51.580467 24.122041,51.585875 24.11973,51.591239 24.118751,51.597633 24.120043,51.60347 24.123843,51.607161 24.126114,51.60995 24.126976,51.616087 24.127133,51.625915 24.125997,51.639776 24.119691,51.576004 24.125605))', 4120).MakeValid().STBuffer(100) 

Answer 1

多邊形是一個閉環。這意味着你的圍欄應該是一條環繞着道路的環。在這種情況下，你的道路下面一條線，然後重複第一點，即

POLYGON((51.576004 24.125605, ... ,51.576004 24.125605)) 

如果您更改爲一個LINESTRING

geography::STGeomFromText('LINESTRING(51.576004 24.125605, 51.580467 24.122041,51.585875 24.11973,51.591239 24.118751,51.597633 24.120043,51.60347 24.123843,51.607161 24.126114,51.60995 24.126976,51.616087 24.127133,51.625915 24.125997,51.639776 24.119691,51.576004 24.125605)', 4120) 

它看起來像這樣

這應該解釋你最終得到的形狀。

要獲得您想要的結果，您可以轉換爲線串，刪除最後一個點，然後應用您的緩衝區。

geography::STGeomFromText('LINESTRING(51.576004 24.125605, 51.580467 24.122041,51.585875 24.11973,51.591239 24.118751,51.597633 24.120043,51.60347 24.123843,51.607161 24.126114,51.60995 24.126976,51.616087 24.127133,51.625915 24.125997,51.639776 24.119691)', 4120).STBuffer(100)