Question

我有一个包含三个文档的收藏集：

{ "_id" : ObjectId("5bfe572882ace71e43703d15"), "event" : "Cdr", "privilege" : "cdr,all", "accountcode" : "", "source" : "22000", "destination" : "98723546", "destinationcontext" : "from-internal", "callerid" : "\"22000\" <22000>", "channel" : "SIP/22000-00000005", "destinationchannel" : "SIP/9144502101-00000006", "lastapplication" : "Dial", "lastdata" : "SIP/9144502101/98723546,300,Tb(func-apply-sipheaders^s^1)", "starttime" : "2018-11-28 15:51:47", "answertime" : "", "endtime" : "2018-11-28 15:51:52", "duration" : "5", "billableseconds" : "0", "disposition" : "NO ANSWER", "amaflags" : "DOCUMENTATION", "uniqueid" : "1543395107.5", "userfield" : "" }
{ "_id" : ObjectId("5bfe5829b3a9321f241f10f2"), "event" : "Cdr", "privilege" : "cdr,all", "accountcode" : "", "source" : "98723546", "destination" : "s", "destinationcontext" : "ivr-1", "callerid" : "\"98723546\" <98723546>", "channel" : "SIP/9144502101-00000007", "destinationchannel" : "", "lastapplication" : "BackGround", "lastdata" : "custom/int1", "starttime" : "2018-11-28 15:56:03", "answertime" : "2018-11-28 15:56:03", "endtime" : "2018-11-28 15:56:09", "duration" : "6", "billableseconds" : "6", "disposition" : "ANSWERED", "amaflags" : "DOCUMENTATION", "uniqueid" : "1543395363.7", "userfield" : "" }
{ "_id" : ObjectId("5bfe5833b3a9321f241f10f4"), "event" : "Cdr", "privilege" : "cdr,all", "accountcode" : "", "source" : "98723546", "destination" : "22000", "destinationcontext" : "from-did-direct", "callerid" : "\"98723546\" <98723546>", "channel" : "SIP/9144502101-00000008", "destinationchannel" : "SIP/22000-00000009", "lastapplication" : "Dial", "lastdata" : "SIP/22000,,HhtrIb(func-apply-sipheaders^s^1)", "starttime" : "2018-11-28 15:56:12", "answertime" : "2018-11-28 15:56:12", "endtime" : "2018-11-28 15:56:19", "duration" : "7", "billableseconds" : "7", "disposition" : "NO ANSWER", "amaflags" : "DOCUMENTATION", "uniqueid" : "1543395372.8", "userfield" : "" }

我想总结$ duration并尝试命令：

db.cdrs.aggregate([{$group: { _id: "$event", total: { $sum: "$duration"}}}])

结果返回：

{ "_id" : "Cdr", "total" : 0 }

如何使用$ sum返回结果三个文档的总和（5 + 6 + 7 = 18）？

Answer 1

Here是您的查询的工作示例，单击顶部的 run 。在您的文档中，持续时间存储为 String ，我想mongoDB不会转换和求和值，请在存储时将持续时间更改为Number。您的查询很好。

Answer 2

您可以通过将sum转换为duration来string Int

它适用于Mongo version 4.0

示例：

db.getCollection('A').aggregate([{
    $addFields: {
      convertedDuration: { $toInt: "$duration" },
   } },
   {
    $group: { _id: "$event", total: { $sum: "$convertedDuration"} } 
   }
])

参考链接：link1，link2

用mongodb对所有文档求和

2 个答案: