Mostly all modern-day web applications have some sort of data storage system at the backend. For example, if you take the case of a web shopping application, data such as the price of an item would be stored in the database.

The Node js framework can work with databases with both relational (such as Oracle and MS SQL Server) and non-relational databases (such as MongoDB). In this tutorial, we will see how we can use databases from within Node js applications.

In this tutorial, you will learn-

• Node.js and NoSQL Databases
• Using MongoDB and Node.js
• How to build a node express app with MongoDB to store and serve content

Node.js and NoSQL Databases

Over the years, NoSQL database such as MongoDB and MySQL have become quite popular as databases for storing data. The ability of these databases to store any type of content and particularly in any type of format is what makes these databases so famous.

Node.js has the ability to work with both MySQL and MongoDB as databases. In order to use either of these databases, you need to download and use the required modules using the Node package manager.

For MySQL, the required module is called “mysql” and for using MongoDB the required module to be installed is “Mongoose.”

With these modules, you can perform the following operations in Node.js

1. Manage the connection pooling – Here is where you can specify the number of MySQL database connections that should be maintained and saved by Node.js.
2. Create and close a connection to a database. In either case, you can provide a callback function which can be called whenever the “create” and “close” connection methods are executed.
3. Queries can be executed to get data from respective databases to retrieve data.
4. Data manipulation, such as inserting data, deleting, and updating data can also be achieved with these modules.

For the remaining topics, we will look at how we can work with MongoDB databases within Node.js.

Using MongoDB and Node.js

As discussed in the earlier topic, MongoDB is one of the most popular databases used along with Node.js.

During this chapter, we will see

How we can establish connections with a MongoDB database

How we can perform the normal operations of reading data from a database as well as inserting, deleting, and updating records in a MongoDB database.

For the purpose of this chapter, let’s assume that we have the below MongoDB data in place.

Database name: EmployeeDB

Collection name: Employee