我如何得到一个map / reduce结果，该结果按照“value”的降序排序。值？如果还使用list函数可以实现吗？ [英] How can I get a map/reduce result which is sorted within descending order of the "value" value?if also using list function can achieve that?

问题描述

我有查看地图并减少如下：
地图：

I have view map and reduce like this: Map:

   function(doc) {
           if(doc.type){
            var usersLength = doc.users.length;
            for (var i = 0; i < usersLength ; i++) {
                    emit([doc.users[i].userid,doc.Service.ownId], 1);
                }
            }
        }

减少：

 function(keys, values, rereduce)
    {
      return sum(values);
    }

然后调用如下视图： _design / aaa / _view / getUserId？group = true& group_level = 2& startkey = [111111]& endkey = [111111，{}]

我可以得到下面的结果集：

I can get the result set below:

{"rows":[
{"key":["111111",""],"value":7},
{"key":["111111","FFFF26"],"value":1},
{"key":["111111","FFFF44"],"value":7},
{"key":["111111","FFFF34"],"value":2}
]}

但是，我想让上面的结果集按value值的降序排序。如果还使用list函数可以实现吗？以下是预期的结果：

However, I want to get the result set above sorted within descending order of the "value" value. if also using list function can achieve that? the following would be expected results:

{"rows":[
{"key":["111111",""],"value":7},
{"key":["111111","FFFF44"],"value":7},
{"key":["111111","FFFF34"],"value":2},
{"key":["111111","FFFF26"],"value":1}
]}

推荐答案

如果要对结果集进行排序，则必须按顺序排序值降序您可以使用比较器回调进行排序：

If you want to sort the result set you have to one that is sorted by value descending you can sort with a comparator callback:

// ES6 Syntax
let originalResult = {
"rows":[
  {"key":["111111",""],"value":7},
  {"key":["111111","FFFF26"],"value":1},
  {"key":["111111","FFFF44"],"value":7},
  {"key":["111111","FFFF34"],"value":2}
]}

let newResult = {
  rows: originalResult.rows.sort((a, b) => b.value - a.value)
} 

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