Mongodb - count of items using addToSet

Question

I grouped by organization and used $addToSet to show the distinct machineIds associated with that organization. I would l

Answer 1

You need to use $size operator in projection like following:

db.collection.aggregate([{
    $group: {
    _id: {
        organization: "$user.organization"
    },
    machineId: {
        "$addToSet": "$user.machineId"
    }
    }
}, {
    $project: {
    "organization": "$_id.organization",
    "machineId": 1,
    "_id": 0,
    "size": {
        $size: "$machineId"
    }
    }
}])