Comparison Operators In MongoDB

MongoDB uses various comparison query operators to compare the values of the documents. The following table contains the comparison query operators:

Matching values using $nin operator:

In this example, we are retrieving only those employee’s documents whose name is not Daisy or Amruta.

//Example

db.q_employee.find({name: {$nin: ["Daisy", "Amruta"]}})

Matching values using $in operator:

In this example, we are retrieving only those employee’s documents whose name is either Daisy or Amruta.

//Example

db.q_employee.find({name: {$in: ["Daisy", "Amruta"]}})

Matching values using $lt operator:

In this example, we are selecting those documents where the value of the vacations field is less than 4.

//Example

db.q_employee.find({vacations: {$lt: 4}})

Matching values using $eq operator:

In this example, we are selecting those documents where the value of the role field is equal to MANAGER.

//Example

db.q_employee.find({ROLE: {$eq: "MANAGER"}})

Matching values using $ne operator:

In this example, we are selecting those documents where the value of the role field is not equal to MANAGER.

//Example

db.q_employee.find({ROLE: {$ne: "MANAGER"}})

Matching values using $gt operator:

In this example, we are selecting those documents where the value of the vacations field is greater than 1.

//Example

db.q_employee.find({vacations: {$gt: 1}})

Matching values using $gte operator:

In this example, we are selecting those documents where the value of the vacations field is greater than equals to 2.

//Example

db.q_employee.find({vacations: {$gte: 2}})

Matching values using $lte operator:

In this example, we are selecting those documents where the value of the vacations field is less than equals to 1.

//Example

db.q_employee.find({vacations: {$lte: 1}})