The Data Model - MongoDB Basics - page 51

Finally, to find items located within a circular shape on a sphere (say, our planet) you
can use the $centerSphere operator. This operator is similar to $center , like so:
> db.restaurants.find( { loc: { $geoWithin : { $centerSphere : [ [52.370524,
5.217682], 10] } } } )
By default, the find() function is ideal for running queries. However, MongoDB also
provides the geoNear() function, which works like the find() function, but also displays
the distance from the specified point for each item in the results. The geoNear() function
also includes some additional diagnostics. The following example uses the geoNear()
function to find the two closest results to the specified position:
> db.runCommand( { geoNear : "restaurants", near : { type : "Point",
coordinates: [52.338433, 5.513629] }, spherical : true})
It returns the following results:
{
"ns" : "stores.restaurants",
"results" : [
{
"dis" : 33155.517810497055,
"obj" : {
"_id" : ObjectId("51ace0f380523d89efd199ac"),
"name" : "Kimono",
"loc" : {
"type" : "Point",
"coordinates" : [
52.370451,
5.217497
]
}
}
},
{
"dis" : 69443.96264213261,
"obj" : {
"_id" : ObjectId("51ace13380523d89efd199ae"),
"name" : "Tokyo Cafe",
"loc" : {
"type" : "Point",
"coordinates" : [
52.368736,
4.89053
]
}
}
},