Mongodb-node.js Tutorial Series

Update many operation in MongoDB using node.js

MongoDB-Nodejs tutorial | Perform mongodb operations using node.js



Overview

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

Let's Start !!
Step 1 - Include Package

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

												
var mongo = require('mongodb');
												
											

Step-2 : Establish Connection

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.

Step-3 : updateMany operation

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

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

An example is given below :

											
//update-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;
	}
	
	//query store the search condition
	var query = { age : {$gt : "22" } };
	//data stores the updated value
	var data = { $set : {age : "above 22" } }
	//CREATING A COLLECTION IN MONGODB USING NODE.JS
	db.collection("details").updateMany(query , data, (err , collection) => {
		if(err) throw err;
		console.log(collection.result.nModified + " Record(s) updated successfully");	//It will console the number of rows updated
		console.log(collection);
		db.close();
	});
});
											
										

You can run the above code using the following command :
											
>node update-many.js
3 Record(s) updated successfully
{ 	result: 
		{ 
			ok: 1,
			n: 3,
			nModified: 3 
		},
	connection: null,
	message: undefined,
	modifiedCount: 3,
	upsertedId: null,
	upsertedCount: 0,
	matchedCount: 3 
 }
											
										

What we learned

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. updateMany() operation in mongodb using node.js