You may consider using Mongo's aggregation framework[1] instead which is zillion times faster[2]. [1] http://docs.mongodb.org/manual/aggregation/ http://docs.m

You may consider using Mongo's aggregation framework[1] instead which is zillion times faster[2]. [1] http://docs.mongodb.org/manual/aggregation/ http://docs.mongodb.org/manual/aggregation/ [2] http://stackoverflow.com/questions/13908438/is-mongodb-aggregation-framework-faster-than-map-reduce http://stackoverflow.com/questions/13908438/is-mongodb-aggre...