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Grouping mongodb aggregation by two fields

I query my database using aggregation and a pipeline with two separate queries:

 $groups_q = array(
            '$group' => array(
                '_id' => '$group_name',
                'total_sum' => array('$sum' => 1)
                )
            );

  $statuses_q = array(
            '$group' => array(
                '_id' => '$user_status',
                'total_sum' => array('$sum' => 1)
                )
            );

$data['statuses'] = $this->mongo_db->aggregate('users',$statuses_q);
$data['groups'] = $this->mongo_db->aggregate('users',$groups_q);

And I get what I want:

Array
(
[statuses] => Array
    (
        [result] => Array
            (
                [0] => Array
                    (
                        [_id] => Inactive
                        [total_sum] => 2
                    )

                [1] => Array
                    (
                        [_id] => Active
                        [total_sum] => 5
                    )

            )

        [ok] => 1
    )

[groups] => Array
    (
        [result] => Array
            (
                [0] => Array
                    (
                        [_id] => Accounting 
                        [total_sum] => 1
                    )

                [1] => Array
                    (
                        [_id] => Administrator
                        [total_sum] => 2
                    )

                [2] => Array
                    (
                        [_id] => Rep
                        [total_sum] => 1
                    )
            )

        [ok] => 1
    )

)

I do not want to query my database twice. Is there a better way to do this? How can I execute it with a single request? Should I use the $ project operator?

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1 answer

You cannot use one aggregate()to execute two grouped counters with the desired result format. After the data has been grouped for the first time, when you no longer have the details necessary to create a second account.

A direct approach is to fulfill two queries, as you already do; -).

, , . _id _ .

mongo:

db.users.aggregate(
    { $group: {
         _id: { group_name: "$group_name", status: "$status" },
         'total_sum': { $sum: 1 }
    }}
)

, , .

+ count, $addToSet .

. find(), group_name status, count .

+13

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