Mongoose Query.prototype.ne() API

The Mongoose Query API.prototype.ne() method of the Mongoose API is used on the Query objects. It allows us to extract the documents where the value of the given field is not equal to the specified values for the field. Let us understand ne() method using an example.

Syntax:

query.ne( path, value );

Parameters: This method accepts two parameters as discussed below:

• path: It is used to specify the field name from the collection.
• value: It is used to specify the value with which you want to compare the document field values.

Return Value: This method returns query object, on which we can call callback function.

Setting up Node.js application:

Step 1: Create a Node.js application using the following command:

npm init

Step 2: After creating the NodeJS application, Install the required module using the following command:

npm install mongoose

Project Structure: The project structure will look like this:

Database Structure: The database structure will look like this, the following documents are present in the collection.

Example 1: In this example, we are illustrating the functionality of ne() method. We are fetching the documents for which the orderNumber value is not equal to 65.

Filename: app.js

Javascript

// Require mongoose module
const mongoose = require("mongoose");

// Set Up the Database connection
const URI = "mongodb://localhost:27017/geeksforgeeks";

const connectionObject = mongoose.createConnection(URI, {
    useNewUrlParser: true,
    useUnifiedTopology: true,
});

const Customer = connectionObject.model(
    "Customer",
    new mongoose.Schema({
        name: String,
        address: String,
        orderNumber: Number,
    })
);

const query = Customer.find();
query.ne("orderNumber", 65);
query.then((res => {
    console.log(res);
})).catch((err) => {
    console.log(err);
})

Step to run the program: To run the application execute the below command from the root directory of the project:

node app.js

Output:

[
  {
    _id: new ObjectId("639ede899fdf57759087a655"),
    name: 'Chintu',
    address: 'Indore',
    orderNumber: 15,
    __v: 0
  },
  {
    _id: new ObjectId("639ede899fdf57759087a653"),
    name: 'Aditya',
    address: 'Mumbai',
    orderNumber: 20,
    __v: 0
  }
]

Example 2: In this example, we are illustrating the functionality of ne() method. We are fetching the documents for which the orderNumber value is not equal to 15 and name value is not equal to “Aditya”.

Filename: app.js

Javascript

// Require mongoose module
const mongoose = require("mongoose");

// Set Up the Database connection
const URI = "mongodb://localhost:27017/geeksforgeeks";

const connectionObject = mongoose.createConnection(URI, {
    useNewUrlParser: true,
    useUnifiedTopology: true,
});

const Customer = connectionObject.model(
    "Customer",
    new mongoose.Schema({
        name: String,
        address: String,
        orderNumber: Number,
    })
);

const query = Customer.find();
query.ne("orderNumber", 15);
query.ne("name", "Aditya");
query.exec((error, result) => {
    if (error) {
        console.log("Error -", error);
    } else {
        console.log("Result -", result);
    }
})

Step to run the program: To run the application execute the below command from the root directory of the project:

node app.js

Output:

Result - [
  {
    _id: new ObjectId("63bcfcc2876922405349b69d"),
    name: 'Bhavesh',
    address: 'Mhow',
    orderNumber: 65,
    __v: 0
  }
]

Reference: https://mongoosejs.com/docs/api/query.html#query_Query-ne