Delete many operation in MongoDB using node.js

In this part of the mongodb operations using node.js tutorial series , we will learn about deleting all the occurrences of data matching a certain criteria from a mongodb collection using node.js .

We will start by including mongodb npm package as shown below :

												
var mongo = require('mongodb');
												
											

Establish a connection between the mongoDb database and our node.js app using the following :

												
var new_db = "mongodb://localhost:27017/demo_db"
												
											

• demo_db is the name of the database. You can change it in accordance with your database name.
• 27017 is the port where mongoDb is running.
• Localhost i.e. 127.0.0.1 is the local IP.

deleteMany() is an inbuilt method of mongodb which is used to delete all the occurrences of data obtained using the search query.
The syntax of deleteMany() function is given below :

										
db.collection("NAME_OF_THE_COLLECTION").deleteMany(SEARCH_CONDITION ,(CALLBACK_FUNCTION) => {});
										
									

											
//delete-many.js
var mongo = require('mongodb');
var new_db = "mongodb://localhost:27017/demo_db"
//connecting to the db
mongo.connect(new_db ,(error , db) => {
	if (error){
		throw error;
	}
	
	//Search query for deletion
	var query = { age : "above 22" };
	
	//Accessing the collection
	db.collection("details").deleteMany(query , (err , collection) => {
		if(err) throw err;
		console.log(collection.result.n + " Record(s) deleted successfully");
		console.log(collection);
		db.close();
	});
});
											
										

											
>node delete-many.js
2 Record(s) deleted successfully
{ 
	result: 
		{ 
			ok: 1,
			n: 2
		},
	connection: null,
	message: undefined,
	deletedCount: 2 
}
											
										

In this article we learned about

1. Including monogdb npm package in your app.
2. Establishing a connection between mongodb database and node.js application.
3. deleteMany() operation in mongodb using node.js