Sort Documents in MongoDB Collection for expert

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MongoDB provides the db.collection.find() method returns a cursor object for the resulted documents. Use the cursor.sort() method or db.collection.find().sort() to sort the resulted documents in a cursor based on the specified order.

Syntax:

db.collection.find().sort(document)

Parameters:

document: A document that defines the sort order in {field: 1, field:-1,...} format where 1 is for ascending order and -1 is for descending order.

The following inserts documents in the employees collection.

Sample Data

db.employees.insertMany([
    { 
        _id:1,
        firstName: "John",
        lastName: "King",
        email: "john.king@abc.com",
        salary: 5000,
        skills: [ "Angular", "React", "MongoDB" ],
        department: { 
                    "name":"IT" 
                }
    },
    { 
        _id:2,
        firstName: "Sachin",
        lastName: "T",
        email: "sachin.t@abc.com",
        salary: 8000,
        skills: [ "Accounting", "Tax" ],
        department: { 
                    "name":"Finance" 
                }
    },
    { 
        _id:3,
        firstName: "James",
        lastName: "Bond",
        email: "jamesb@abc.com",
        salary: 7500,
        skills: [ "Sales", "Marketing" ],
        department: { 
                    "name":"Marketing" 
                }
    },
    { 
        _id:4,
        firstName: "Steve",
        lastName: "J",
        email: "steve.j@abc.com",
        salary: 7000

    },
    { 
        _id:5,
        firstName: "Kapil",
        lastName: "D",
        email: "kapil.d@abc.com",
        salary: 4500,
        skills: [ "Accounting", "Tax" ],
        department: { 
                    "name":"Finance" 
                }

    },
    { 
        _id:6,
        firstName: "Amitabh",
        lastName: "B",
        email: "amitabh.b@abc.com",
        salary: 7000
    }
])

The following example sorts the employees collection in the ascending order of the firstName field.

Example: sort() Copy

db.employees.find().sort({ firstName:1 })

Output

[
  {
    _id: 6,
    firstName: 'Amitabh',
    lastName: 'B',
    email: 'amitabh.b@abc.com',
    salary: 7000
  },
  {
    _id: 3,
    firstName: 'James',
    lastName: 'Bond',
    email: 'jamesb@abc.com',
    salary: 7500,
    skills: [ 'Sales', 'Marketing' ],
    department: { name: 'Marketing' }
  },
  {
    _id: 1,
    firstName: 'John',
    lastName: 'King',
    email: 'john.king@abc.com',
    salary: 5000,
    skills: [ 'Angular', 'React', 'MongoDB' ],
    department: { name: 'IT' }
  },
  {
    _id: 5,
    firstName: 'Kapil',
    lastName: 'D',
    email: 'kapil.d@abc.com',
    salary: 4500,
    skills: [ 'Accounting', 'Tax' ],
    department: { name: 'Finance' }
  },
  {
    _id: 2,
    firstName: 'Sachin',
    lastName: 'T',
    email: 'sachin.t@abc.com',
    salary: 8000,
    skills: [ 'Accounting', 'Tax' ],
    department: { name: 'Finance' }
  },
  {
    _id: 4,
    firstName: 'Steve',
    lastName: 'J',
    email: 'steve.j@abc.com',
    salary: 7000
  }
]

You can use the cursor object to sort the result. The following returns the same result as above.

Example: cursor.sort()

var cursor = db.employees.find()
cursor.sort({ firstName:1 })

The following example list the sorting on different fields.

Example: sort()

db.employees.find().sort({ _id: -1 })// sorts by descending order of _id
db.employees.find().sort({ salary: -1 })// sorts by descending order of salary
db.employees.find({salary: {$gt:5000}}).sort({ salary: -1 })// find where salary > 5000 and sorts the result by descending order of salary
db.employees.find().sort({ firstName:1, salary: -1 })// sorts by ascending order of firstName and descending order of salary
db.employees.find().sort({"department.name":1}) // sorts by embedded doc department.name

MongoDB uses the following comparison order, from lowest to highest for comparing values of different BSON types.