Group by sum mongodb
mongodb
Solution
You're close, but you need to use a `$sum` operator to count the groupings:
db.users.aggregate([ {
$group: {
_id: "$status",
amt: { $sum: 1 }
}
} ] )
Problem
This is my old MySQL query. ``` SELECT Count(`status`) as amt, `status` FROM (`users`) GROUP BY `status` ``` Which would return something like ``` +---------+----------+ | amt | status | +---------+----------+ | 3 | 0 | | 210 | 1 | | 330 | 2 | | 4233 | 3 | | 540085 | 4 | +---------+----------+ ``` This seems like the most basic of Mongo queries ever, but after many tries using `$group` then told to use `$aggregate` I still have no luck. ``` db.users.aggregate([ { $group: { _id: "$status", amt: { $status: 1 } } } ] ) ``` I thought this would work as selecting the status field, but since I included the $, it would count the amount of those grouped queries via the ` amt: { $status : 1 } but my response is only ``` { "result" : [ ], "ok" : 1 } ``` so it semi worked? but didn't return anything. I thought that is what the `_id` part was for. I was following this example: http://docs.mongodb.org/manual/reference/aggregation/group/