Connecting a Hostinger MySQL Database to a Node.js Application

Overview

This guide explains how to connect a Node.js application to a MySQL database hosted on Hostinger.

Before proceeding:

• You already have a built Node.js website or application

• Your app requires a database connection to store data

• You are ready to configure the database and environment variables for production

Step 1: Create a MySQL Database in hPanel

1. Log in to Hostinger hPanel

2. Navigate to Databases → MySQL Databases

3. Click Create Database

4. Fill in:

   • Database name

   • Database username

   • Password (save this securely)

5. Click Create

Once created, note down:

• Database name

• Database username

• Database password

• Database host (usually localhost on Hostinger)

Step 2: Configure Environment Variables

Your Node.js app should never hardcode database credentials.

Instead, use environment variables.

Option A: Separate Environment Variables (Recommended for clarity)

Create or update your .env file:

DB_HOST=localhost
DB_PORT=3306
DB_USER=databaseuser
DB_PASSWORD=databasepassword
DB_NAME=databasename

Option B: Single Database Connection String

You can also define one database connection variable, depending on your application setup:

In this article, we’ll be using Option A.

Step 3: Rebuild or Restart the Application

After updating environment variables, make sure to restart your application so it loads the new values.

Restart from hPanel (Recommended)

For server-side Node.js apps (e.g., Express.js, Next.js, NestJS), you can restart directly from the dashboard:

1. Open your Website Dashboard in hPanel
2. Click Restart
   
   

Alternative: Restart via SSH

If you prefer to restart via the command line:

• Connect to SSH
• Run: cd domains/xx/public_html (replace xx with your domain name)
• Run: touch tmp/restart.txt

Step 4: Ensure Your Website Contains Database Connection Files

Before your application can store or retrieve data, it must include a dedicated database connection file.

This file is responsible for:

• Reading database credentials from environment variables

• Establishing a connection to the MySQL database

• Exporting the connection so it can be reused across the application

Keeping database logic in a single file makes the application easier to maintain and debug.

Typical Database Connection File Structure

In most Node.js projects, the database connection file is located in a folder such as:

• config/database.js

• db.js

• database/connection.js

The exact name does not matter, as long as it is imported where needed.

Default MySQL Connection File Example (Node.js)

Below is a simple and commonly used example using the mysql2 package.

import mysql from "mysql2/promise";
const db = mysql.createPool({
  host: process.env.DB_HOST,
  port: process.env.DB_PORT || 3306,
  user: process.env.DB_USER,
  password: process.env.DB_PASSWORD,
  database: process.env.DB_NAME,
});
export default db;

This file:

• Reads credentials from environment variables

• Creates a reusable connection pool

• Prevents opening a new connection for every query

Example Using a Single Connection String

If your application uses one database connection variable, the connection file may look like this:

import mysql from "mysql2/promise";

const db = mysql.createPool(process.env.DATABASE_URL);

export default db;

Example connection string:

DATABASE_URL=mysql://databaseuser:databasepassword@localhost:3306/databasename

Using the Database Connection in Your Application

Once the connection file exists, it can be imported and used anywhere in your project.

Example:

import db from "./config/database.js";

const [rows] = await db.query("SELECT * FROM users");

This confirms that:

• The database connection file is correctly set up

• Your application can communicate with the MySQL database

Step 5: Create Required Database Tables

Before storing data, your database must contain the required tables and columns.

Example SQL table

CREATE TABLE users (
id INT AUTO_INCREMENT PRIMARY KEY,
name VARCHAR(255) NOT NULL,
email VARCHAR(255) NOT NULL UNIQUE,
created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

You can execute this SQL:

• Via phpMyAdmin in hPanel

• Or programmatically from your application

Step 6: Test Data Insertion in Production

1. Open your live Node.js application

2. Perform an action that stores data (e.g., submit a form)

3. Check the database using phpMyAdmin

4. Confirm:

   • A new row is created

   • Values are stored correctly

Common Issues & Troubleshooting

❌ Access denied for user

• Verify database username and password

• Ensure the user is assigned to the database

❌ Cannot connect to MySQL server

• Confirm host is set to localhost

• Ensure port 3306 is used

❌ Environment variables not loading

• Restart the Node.js application

• Confirm .env is included in the runtime environment