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mongodbgeometrypointgeo

MongoDB How to find which polygon contains a specified Point?

I insert many polygons into MongoDB(2.4.8), and hope find the polygon a specified Point sits in. It seems a common question. But after reading all docs from google, I didn't get the result. So create this question.

e.g.

db.addr_poly.insert(
{ loc :
   { type : "Polygon" ,
     coordinates : [ [ [ 0 , 0 ] , [ 3 , 6 ] , [ 6 , 1 ] , [ 0 , 0 ] ] ]
} })
db.addr_poly.insert(
{ loc :
   { type : "Polygon" ,
     coordinates : [ [ [ 0 , 0 ] , [ -3 , -6 ] , [ -6 , -1 ] , [ 0 , 0 ] ] ]
} })

Now how to find the polygon which contains Point(1,1)?

Anybody can help me? Thanks a lot!

Solution

  • Use the $geoIntersects operator. It queries for all shapes which intersect the GeoJSON object you pass. When you pass a point to it, it should return all shapes which include that point. Keep in mind that the $geoIntersects operator only works for 2dsphere indexes, not for 2d indexes.