apalexo

Thanks for your reply. I need to use aggregate (http://docs.mongodb.org/manual/tutorial/aggregation-with-user-preference-data) - in mongodb aggregate make result more shortest than group and group not work in sharded db.

For example, I try this: mongodb:exec_cmd(def,"testdb">>, [{aggregate, [{, },{ , [{,}]}, {,[{,},{,[{,}]}]}]}]) But result -