是否有可能做出這樣的計算並將結果返回給MongoDB？

Question

我對MongoDB很新。考慮下面的集合：

{ 
"_id" : ObjectId("c0c672fa6db9b3f954732b1a"), 
"date" : ISODate("2016-11-12T00:00:00.000Z"), 
"statistics" : { 
    "members" : { 
     "topPerformers" : { 
      "hours" : [ 
       { 
        "workHour" : 10, 
        "Darth Vader" : 72, 
        "Walrus Man" : 80, 
        "Imperial Stromtrooper" : 60 
       }, 
       { 
        "workHour" : 11, 
        "Darth Vader" : 142, 
        "Walrus Man" : 115, 
        "Imperial Stromtrooper" : 100 
       }, 
       { 
        "workHour" : 12, 
        "Darth Vader" : 116, 
        "Walrus Man" : 81, 
        "Imperial Stromtrooper" : 113 
       }, 
       { 
        "workHour" : 13, 
        "Darth Vader" : 128, 
        "Walrus Man" : 90, 
        "Imperial Stromtrooper" : 141 
       }, 
       { 
        "workHour" : 14, 
        "Darth Vader" : 95, 
        "Walrus Man" : 118, 
        "Imperial Stromtrooper" : 116 
       }, 
       { 
        "workHour" : 15, 
        "Darth Vader" : 91, 
        "Walrus Man" : 93, 
        "Imperial Stromtrooper" : 124 
       }, 
       { 
        "workHour" : 16, 
        "Darth Vader" : 144, 
        "Walrus Man" : 95, 
        "Imperial Stromtrooper" : 111 
       }, 
       { 
        "workHour" : 17, 
        "Darth Vader" : 143, 
        "Walrus Man" : 72, 
        "Imperial Stromtrooper" : 136 
       }, 
       { 
        "workHour" : 18, 
        "Darth Vader" : 54, 
        "Walrus Man" : 88, 
        "Imperial Stromtrooper" : 87 
       }, 
       { 
        "workHour" : 19, 
        "Darth Vader" : 82, 
        "Walrus Man" : 146, 
        "Imperial Stromtrooper" : 67 
       }, 
       { 
        "workHour" : 20, 
        "Darth Vader" : 88, 
        "Walrus Man" : 136, 
        "Imperial Stromtrooper" : 52 
       }, 
       { 
        "workHour" : 21, 
        "Darth Vader" : 92, 
        "Walrus Man" : 113, 
        "Imperial Stromtrooper" : 124 
       }, 
       { 
        "workHour" : 22, 
        "Darth Vader" : 91, 
        "Walrus Man" : 68, 
        "Imperial Stromtrooper" : 128 
       }, 
       { 
        "workHour" : 23, 
        "Darth Vader" : 125, 
        "Walrus Man" : 64, 
        "Imperial Stromtrooper" : 84 
       }, 
       { 
        "workHour" : 0, 
        "Darth Vader" : 97, 
        "Walrus Man" : 108, 
        "Imperial Stromtrooper" : 75 
       } 
      ] 
     } 
    } 
} 
} 

1天每一個記錄是這樣的，比如我有收集每天在30份文件。我可以用我想要的日期範圍做db.getCollection('name').find({ date: { $gte: new ISODate(), $lt: new ISODate() } })，然後如果我選擇了整個月的記錄，我可以循環使用statistics.members.topPerformers.hours並計算當天每個成員在客戶端的總數，如下所示：

statistics.members.topPerformers.hours.forEach((hour) => { 
      Object 
      .keys(hour) 
      .filter(key => key !== 'workHour') 
      .forEach((key) => { 
       result[key] = (result[key] || 0) + hour[key]; 
      }); 
     }); 

我能做到這一點的服務器端與蒙戈並返回修改後的結果是這樣一個例子：

{ 
"_id" : ObjectId("c0c672fa6db9b3f954732b1a"), 
"date" : ISODate("2016-11-12T00:00:00.000Z"), 
"statistics" : { 
    "members" : { 
     "topPerformers" : { 
      "hours" : [ 
       { 
        "workHour" : 10, 
        "Darth Vader" : 2512, 
        "Walrus Man" : 1423, 
        "Imperial Stromtrooper" : 1487 
       }, 
      ] 
      } 
     } 
    } 

Answer 1

你可以運行聚合管道，它利用了$match操作流水線階段來過濾col中的文檔以前的$unwind運算符可以將嵌入的小時數組展平，然後您可以使用管道對非規格化文檔進行分組並計算總和。

以下蒙戈外殼操作演示上面：

var start = new Date(); 
start.setHours(0,0,0,0); 

var end = new Date(); 
end.setHours(23,59,59,999); 

db.collection.aggregate([ 
    { "$match": { "date": { "$gte": start, "$lte": end } } }, 
    { "$unwind": "$statistics.members.topPerformers.hours" }, 
    { 
     "$group": { 
      "_id": "$_id", 
      "date": { "$first": "$date" }, 
      "workHour" : { 
       "$sum": "$statistics.members.topPerformers.hours.workHour" 
      }, 
      "Darth Vader" : { 
       "$sum": "$statistics.members.topPerformers.hours.Darth Vader" 
      }, 
      "Walrus Man" : { 
       "$sum": "$statistics.members.topPerformers.hours.Walrus Man" 
      }, 
      "Imperial Stromtrooper" : { 
       "$sum": "$statistics.members.topPerformers.hours.Imperial Stromtrooper" 
      } 
     } 
    } 
]); 

樣本輸出

{ 
    "_id" : ObjectId("c0c672fa6db9b3f954732b1a"), 
    "date" : ISODate("2016-11-12T00:00:00.000Z"), 
    "workHour" : 231.0, 
    "Darth Vader" : 1560.0, 
    "Walrus Man" : 1467.0, 
    "Imperial Stromtrooper" : 1518.0 
} 

---

雖然不是必需的，你可以重塑通過附加一個$project最後文件領域管道如下

db.collection.aggregate([ 
    { "$match": { "date": { "$gte": start, "$lte": end } } }, 
    { "$unwind": "$statistics.members.topPerformers.hours" }, 
    { 
     "$group": { 
      "_id": "$_id", 
      "date": { "$first": "$date" }, 
      "workHour" : { 
       "$sum": "$statistics.members.topPerformers.hours.workHour" 
      }, 
      "Darth Vader" : { 
       "$sum": "$statistics.members.topPerformers.hours.Darth Vader" 
      }, 
      "Walrus Man" : { 
       "$sum": "$statistics.members.topPerformers.hours.Walrus Man" 
      }, 
      "Imperial Stromtrooper" : { 
       "$sum": "$statistics.members.topPerformers.hours.Imperial Stromtrooper" 
      } 
     } 
    }, 
    { 
     "$project": { 
      "date": 1, 
      "statistics.members.topPerformers.hours.workHour": "$workHour",, 
      "statistics.members.topPerformers.hours.Darth Vader": "$Darth Vader", 
      "statistics.members.topPerformers.hours.Walrus Man": "$Walrus Man", 
      "statistics.members.topPerformers.hours.Imperial Stromtrooper": "$Imperial Stromtrooper" 
     } 
    } 
]) 

輸出

{ 
    "_id" : ObjectId("c0c672fa6db9b3f954732b1a"), 
    "date" : ISODate("2016-11-12T00:00:00.000Z"), 
    "statistics" : { 
     "members" : { 
      "topPerformers" : { 
       "hours" : { 
        "workHour" : 231.0, 
        "Darth Vader" : 1560.0, 
        "Walrus Man" : 1467.0, 
        "Imperial Stromtrooper" : 1518.0 
       } 
      } 
     } 
    } 
}