Azure 如何计算cosmos DB中的不同值

我在Cosmos DB中创建了一些文档，如下所示：

[
  {
    "class": "class01",
    "student": {
      "lastReport": [
        {
          "Name": "st01",
          "score": "C"
        },
        {
          "Name": "st02",
          "score": "B"
        }
      ],
      "lastTime": "2018-05-10"
    }
  },
  {
    "class": "class02",
    "student": {
      "lastReport": [
        {
          "Name": "st03",
          "score": "C"
        },
        {
          "Name": "st01",
          "score": "A"
        }
      ],
      "lastTime": "2018-05-10"
    }
  },
  {
    "class": "class01",
    "student": {
      "lastReport": [
        {
          "Name": "st01",
          "score": "C"
        },
        {
          "Name": "st02",
          "score": "A"
        },
        {
          "Name": "st03",
          "score": "B"
        }
      ],
      "lastTime": "2018-05-10"
    }
  }
]

[
  {
    "score": "C",
    "Num" : 3
  },
{
    "score": "B",
    "Num" : 2
  },
{
    "score": "A",
    "Num" : 2
  }
  ]

你能帮我计算所有数据中的分数值吗？我的期望是这样的结果：

[
  {
    "class": "class01",
    "student": {
      "lastReport": [
        {
          "Name": "st01",
          "score": "C"
        },
        {
          "Name": "st02",
          "score": "B"
        }
      ],
      "lastTime": "2018-05-10"
    }
  },
  {
    "class": "class02",
    "student": {
      "lastReport": [
        {
          "Name": "st03",
          "score": "C"
        },
        {
          "Name": "st01",
          "score": "A"
        }
      ],
      "lastTime": "2018-05-10"
    }
  },
  {
    "class": "class01",
    "student": {
      "lastReport": [
        {
          "Name": "st01",
          "score": "C"
        },
        {
          "Name": "st02",
          "score": "A"
        },
        {
          "Name": "st03",
          "score": "B"
        }
      ],
      "lastTime": "2018-05-10"
    }
  }
]

[
  {
    "score": "C",
    "Num" : 3
  },
{
    "score": "B",
    "Num" : 2
  },
{
    "score": "A",
    "Num" : 2
  }
  ]

---

Cosmos DB本机不支持Group by，因此没有现成的方法来执行此查询

然而，documentdb lumenize允许您使用存储过程来实现这一点。我自己也没用过，但可能值得一看

链接是：

---

正如@Sajeetharan所说，到目前为止，azure cosmos db不支持Groupby。但是，我建议您使用

存储过程
来实现您的需求

基于您的示例文档，我向您提供了一个示例存储过程。请参考它

function sample() {
    var collection = getContext().getCollection();
    var isAccepted = collection.queryDocuments(
        collection.getSelfLink(),
        'SELECT a.score FROM  c join a in c.student.lastReport',
        function (err, feed, options) {
            if (err) throw err;
            if (!feed || !feed.length) getContext().getResponse().setBody('no docs found');
            else {
                var map = {};
                var returnResult = [];
                for(var i = 0;i<feed.length;i++){
                    var s = feed[i].score;
                    if(map.hasOwnProperty(s)){
                        map[s] ++;   
                    }else {
                        map[s] = 1;   
                    }         
                }

                for(var key in map){
                    console.log(key)
                    var obj = {
                        "score":key,
                        "num" : map[key]
                    };
                    returnResult.push(obj);
                }
                getContext().getResponse().setBody(returnResult);
            }
        });

    if (!isAccepted) throw new Error('The query was not accepted by the server.');
}

函数示例（）{
var collection=getContext（）.getCollection（）；
var isAccepted=collection.queryDocuments(
collection.getSelfLink（），
'从c中选择a.score在c.student.lastReport中加入a'，
功能（错误、馈送、选项）{
如果（错误）抛出错误；
如果（！feed | |！feed.length）getContext（）.getResponse（）.setBody（'未找到文档'）；
否则{
var-map={}；
var returnResult=[]；
对于（var i=0；igroupby），现在在cosmosDB中是可能的
此文档包含所有详细信息
可能重复@Sajeetharan我认为这个问题与我的不同question@leon是的，它不同，但答案是sameI saw，这不是同一个答案。他想数一份文件，但我想数所有文件