mongodb - use geoNear without omitting non 2dsphere indexed rows - mongodb

Question

When using geoNear, all rows which do not have location (not a part of 2dsphere index) are omitted.
How to use geoNear to get nearest results but also show other rows that do not have location? The rows which do not have a location should be ranked lower in the results.
.collection('users')
.aggregate([
{
$geoNear: {
near: { type: "Point", coordinates: [userLocArray[0], userLocArray[1]]},
distanceField: "dist.calculated",
spherical: true,
//maxDistance: matchDistance,
}
},
Example documents (In the example below, the users xyz and mmm are omitted by geoNear because they do not have location field. I just wanted them to be ranked lowest but not completely omitted.
db={
users: [
{
_id: "abc",
name: "abc",
group: 1,
location: {
type: "Point",
coordinates: [
53.23,
67.12
]
},
calculatedDist: 112
},
{
_id: "xyz",
name: "xyyy",
group: 1,
calculatedDist: 13
},
{
_id: "123",
name: "yyy",
group: 1,
location: {
type: "Point",
coordinates: [
54.23,
67.12
]
},
calculatedDist: 13
},
{
_id: "rrr",
name: "tttt",
group: 1,
location: {
type: "Point",
coordinates: [
51.23,
64.12
]
},
calculatedDist: 14
},
{
_id: "mmm",
name: "mmmm",
group: 1,
calculatedDist: 14
},
]
}

Answer 1

You can simply add another $match stage at the end of pipeline to choose those documents without location
db.users.aggregate([
{
"$geoNear": {
"near": {
"type": "Point",
"coordinates": [
53.23,
67.12
]
},
"distanceField": "d"
}
},
{
"$unionWith": {
"coll": "users",
"pipeline": [
{
"$match": {
"location": null
}
}
]
}
}
])
Yes, you are right that Mongo Playground cannot demonstrate 2d sphere index behaviour. But I put it here nevertheless.