Question

I am using the $in clause within a mongodb query. However, I want my results to be ordered exactly as my input list used in the $in clause.

The results I get back are in the order the objects were inserted.

All the documentation I have read so far tells me that the sort cursor function only works with document fields. Does this mean that I cannot do the above?

Answer 1

MongoDB does not insert in any particular order. You can sort your results though.

See:

http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%24in

db.updates.ensureIndex( { ts : 1 } ); // ts == timestamp
var myFriends = myUserObject.friends; // let's assume this gives us an array of DBRef's of my friends
var latestUpdatesForMe = db.updates.find( { user : { $in : myFriends } } ).sort( { ts : -1 } ).limit(10);