How Do I Calculate the Area of a Polygon in a MySQL Database When the Polygon's Points are Lat Longs? -

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How do I calculate the area of ​​a polygon stored in a MySQL database? Pieces of polygon are long long. Therefore, there is a problem in degree and minute.

I tried: 

  `my_table` from SELECT AREA (my_polygon) where name = 'newport'

because, Points are long, I get strange results.

(I can not switch to Postgrowth). Is there a way to do this in MySQL? I want to get results in square meters or square km or square mile - none of these will be fine.

You have to change those latters and be long in the more appropriate coordination system.

Since the earth is a spherical, so you are talking about calculating an area in spherical coordinates.

Documents say that MySQL takes a polygon as its input, I would say that if you want something like square mile to area then you have the equivalent surface of your latitude / long coordinate (x, y ) Should coordinate with the right units (like miles). Then pass those areas in the array function.

It suggests that someone has faced this problem and has solved it.


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