Mongodb地理空间索引

db.places.insert(
   {
      loc : { type: "Point", coordinates: [ -73.97, 40.77 ] },
      name: "Central Park",
      category : "Parks"
   }
)

db.places.insert(
   {
      loc : { type: "Point", coordinates: [ -73.88, 40.78 ] },
      name: "La Guardia Airport",
      category : "Airport"
   }
)

db.places.ensureIndex( { loc : "2dsphere" } )

db.places.ensureIndex( { loc : "2dsphere" , category : -1, name: 1 } )

3. 查询

db.places.find( { loc :
                  { $geoWithin :
                    { $geometry :
                      { type : "Polygon" ,
                        coordinates : [ [
                                          [ 0 , 0 ] ,
                                          [ 3 , 6 ] ,
                                          [ 6 , 1 ] ,
                                          [ 0 , 0 ]
                                        ] ]
                } } } } )

3.2 查询附近的值

 db.places.find( { loc :
                         { $near :
                           { $geometry :
                              { type : "Point" ,
                                coordinates : [ <longitude> , <latitude> ] } ,
                             $maxDistance : <distance in meters>
                      } } } )

3.3 查询圆形内的值

db.places.find( { loc :
                  { $geoWithin :
                    { $centerSphere :
                       [ [ -88 , 30 ] , 10 ]
                } } } )