Node.js MongoDB Sort

排序记录集

使用 sort() 方法按升序或降序对记录集进行排序。

sort() 方法接受一个参数,即定义排序顺序的对象。

实例

按名称的字母顺序对记录集排序:

var MongoClient = require('mongodb').MongoClient;
var url = "mongodb://localhost:27017/";

MongoClient.connect(url, function(err, db) {
  if (err) throw err;
  var dbo = db.db("mydb");
  var mysort = { name: 1 };
  dbo.collection("customers").find().sort(mysort).toArray(function(err, result) {
    if (err) throw err;
    console.log(result);
    db.close();
  });
});
运行实例 »

将上述代码保存在名为 "demo_sort.js" 的文件中,然后运行该文件:

运行 "demo_sort.js"

C:\Users\Your Name>node demo_sort.js

返回结果:

[
  { _id: 58fdbf5c0ef8a50b4cdd9a86, name: 'Amy', address: 'Apple st 652'},
  { _id: 58fdbf5c0ef8a50b4cdd9a8e, name: 'Ben', address: 'Park Lane 38'},
  { _id: 58fdbf5c0ef8a50b4cdd9a8a, name: 'Betty', address: 'Green Grass 1'},
  { _id: 58fdbf5c0ef8a50b4cdd9a90, name: 'Chuck', address: 'Main Road 989'},
  { _id: 58fdbf5c0ef8a50b4cdd9a87, name: 'Hannah', address: 'Mountain 21'},
  { _id: 58fdbf5c0ef8a50b4cdd9a84, name: 'John', address: 'Highway 71'},
  { _id: 58fdbf5c0ef8a50b4cdd9a88, name: 'Michael', address: 'Valley 345'},
  { _id: 58fdbf5c0ef8a50b4cdd9a85, name: 'Peter', address: 'Lowstreet 4'},
  { _id: 58fdbf5c0ef8a50b4cdd9a8b, name: 'Richard', address: 'Sky st 331'},
  { _id: 58fdbf5c0ef8a50b4cdd9a89, name: 'Sandy', address: 'Ocean blvd 2'},
  { _id: 58fdbf5c0ef8a50b4cdd9a8c, name: 'Susan', address: 'One way 98'},
  { _id: 58fdbf5c0ef8a50b4cdd9a8d, name: 'Vicky', address: 'Yellow Garden 2'},
  { _id: 58fdbf5c0ef8a50b4cdd9a91, name: 'Viola', address: 'Sideway 1633'},
  { _id: 58fdbf5c0ef8a50b4cdd9a8f, name: 'William', address: 'Central st 954'}
]


降序

在排序对象中使用值 -1 进行降序排序。

{ name: 1 } // 升序
{ name: -1 } // 降序

实例

按名称的字母顺序对记录集进行反向排序:

var MongoClient = require('mongodb').MongoClient;
var url = "mongodb://localhost:27017/";

MongoClient.connect(url, function(err, db) {
  if (err) throw err;
  var dbo = db.db("mydb");
  var mysort = { name: -1 };
  dbo.collection("customers").find().sort(mysort).toArray(function(err, result) {
    if (err) throw err;
    console.log(result);
    db.close();
  });
});
运行实例 »

将上述代码保存在名为 "demo_sort_desc.js" 的文件中,然后运行该文件:

运行 "demo_sort_desc.js"

C:\Users\Your Name>node demo_sort_desc.js

返回结果:

[
  { _id: 58fdbf5c0ef8a50b4cdd9a8f, name: 'William', address: 'Central st 954'},
  { _id: 58fdbf5c0ef8a50b4cdd9a91, name: 'Viola', address: 'Sideway 1633'},
  { _id: 58fdbf5c0ef8a50b4cdd9a8d, name: 'Vicky', address: 'Yellow Garden 2'},
  { _id: 58fdbf5c0ef8a50b4cdd9a8c, name: 'Susan', address: 'One way 98'},
  { _id: 58fdbf5c0ef8a50b4cdd9a89, name: 'Sandy', address: 'Ocean blvd 2'},
  { _id: 58fdbf5c0ef8a50b4cdd9a8b, name: 'Richard', address: 'Sky st 331'},
  { _id: 58fdbf5c0ef8a50b4cdd9a85, name: 'Peter', address: 'Lowstreet 4'},
  { _id: 58fdbf5c0ef8a50b4cdd9a88, name: 'Michael', address: 'Valley 345'},
  { _id: 58fdbf5c0ef8a50b4cdd9a84, name: 'John', address: 'Highway 71'},
  { _id: 58fdbf5c0ef8a50b4cdd9a87, name: 'Hannah', address: 'Mountain 21'},
  { _id: 58fdbf5c0ef8a50b4cdd9a90, name: 'Chuck', address: 'Main Road 989'},
  { _id: 58fdbf5c0ef8a50b4cdd9a8a, name: 'Betty', address: 'Green Grass 1'},
  { _id: 58fdbf5c0ef8a50b4cdd9a8e, name: 'Ben', address: 'Park Lane 38'},
  { _id: 58fdbf5c0ef8a50b4cdd9a86, name: 'Amy', address: 'Apple st 652'}
]