Question

我有查看地图并减少如下：地图：

   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);
    }

然后调用这样的视图：_design/aaa/_view/getUserId?group=true&group_level=2&startkey=["111111"]&endkey=["111111",{}]

我可以得到下面的结果集：

{"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：

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

Answer 1

如果要对结果集进行排序，必须按值降序排序，可以使用比较器回调进行排序：

// 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)
}

如何获得按“值”值的降序排序的map / reduce结果？如果还使用list函数可以实现吗？

1 个答案: