mongodb组每2周一次

时间:2014-01-17 13:38:07

标签: mongodb mongoid aggregation-framework

这是每周分组数据的方法:

 transactions.aggregate({   
    [
        {$match: {status: "committed"}},
        {$group: {
            _id: {
                $year: "$date",                                 
                $week: "$date"                          
            },
            count: {$sum: 1},
            start_date: {$min: "$date"},
            end_date: {$max: "$date"}                               
        }}
    ]
});     

问题是,如何每两周进行一次分组并获得统计数据?

谢谢。

根据接受的答案正确的方式

感谢Mzzl,这适用于每两周一次的分组。以下是完整版本。

db.transactions.aggregate([
    {$match: {status: "committed"}},
    {$project: {
        twoweekperiod: {
            $subtract: [
              {$week: "$date"}, {$mod: [{$week: "$date"}, 2] }
            ]
        },
        date:1,
        status:1
   }},
   {$group: {
        _id: {
            year: {$year: "$date"},                                 
            twoweek: "$twoweekperiod"                      
        },
        count: {$sum: 1},
        start_date: {$min: "$date"},
        end_date: {$max: "$date"}                               
    }}
])

1 个答案:

答案 0 :(得分:9)

假设$ week包含周数,您可以创建一个“每两周一次”的数字,并按此分组。尝试这样的事情:

{ 
    $project: {
        twoweekperiod: {
            $subtract: [
              '$week', {$mod: ['$week', 2] }
            ]
        }, status:1, date:1, etc...
   }
}

我不知道在mongo查询中进行整数除法的方法,所以我从周数中减去weeknumber mod 2,得到一个每隔一周而不是每周更改的数字。然后,您可以尝试按此编号进行分组。