Aggregate.sort(object: Object): Aggregate

支持端:小程序 2.7.4, 云函数 0.8.1, Web

聚合阶段。根据指定的字段,对输入的文档进行排序。

参数

object: Object

返回值

Aggregate

API 说明

形式如下:

sort({
    <字段名1>: <排序规则>,
    <字段名2>: <排序规则>,
})

<排序规则>可以是以下取值:

  • 1 代表升序排列(从小到大);
  • -1 代表降序排列(从大到小);

示例

升序/降序排列

假设我们有集合 articles,其中包含数据如下:

{ "_id": "1", "author": "stark",  "score": 80, "age": 18 }
{ "_id": "2", "author": "bob",    "score": 60, "age": 18 }
{ "_id": "3", "author": "li",     "score": 55, "age": 19 }
{ "_id": "4", "author": "jimmy",  "score": 60, "age": 22 }
{ "_id": "5", "author": "justan", "score": 95, "age": 33 }
db.collection('articles')
  .aggregate()
  .sort({
      age: -1,
      score: -1
  })
  .end()

上面的代码在 students 集合中进行聚合搜索,并且将结果排序,首先根据 age 字段降序排列,然后再根据 score 字段进行降序排列。

输出结果如下:

{ "_id": "5", "author": "justan", "score": 95, "age": 33 }
{ "_id": "4", "author": "jimmy",  "score": 60, "age": 22 }
{ "_id": "3", "author": "li",     "score": 55, "age": 19 }
{ "_id": "1", "author": "stark",  "score": 80, "age": 18 }
{ "_id": "2", "author": "bob",    "score": 60, "age": 18 }