Mongoose sort, ascending and $exists
You can make use of aggregation here. So, you have a collection called task.
Task Table Data
| id | track || --------------- | ------------------------ || someid_1 | { "nextRun" : 10 } || someid_2 | { } || someid_3 | { "nextRun" : 3 } |Now, as per your requirement, out put should be-
| id | track || ------------ | ------------------ || someid_3 | { "nextRun" : 3 } || someid_1 | { "nextRun" : 10 } || someid_2 | { } |Mongodb Query
db.getCollection('Task').aggregate([{ $project: { _id: 1, track: 1, nextRunExists: { $cond: [ { $ifNull: ["$track.nextRun", false]}, 1, 0 ] } }}, { $sort: { nextRunExists: -1, track: 1 }}])