Connection with MySql Database

Connecting to a MySQL database using PHP is a common task for web developers. The connection process involves several steps: setting up the MySQL server, creating a database and a user, and then writing PHP code to establish the connection.

Here’s a step-by-step guide:

Step 1: Set Up MySQL Server

Before you can connect to a MySQL database, you need to have MySQL installed and running on your server. You can download and install MySQL from the official MySQL website.

Step 2: Create a Database and User

Log in to your MySQL server and create a database and a user with appropriate privileges. This can be done using the MySQL command line or a tool like phpMyAdmin.

Using MySQL Command Line

— Log in to MySQL server as root

mysql -u root -p

— Create a new database

CREATE DATABASE my_database;

— Create a new user and grant privileges

CREATE USER ‘my_user’@’localhost’ IDENTIFIED BY ‘my_password’;

GRANT ALL PRIVILEGES ON my_database.* TO ‘my_user’@’localhost’;

FLUSH PRIVILEGES;

— Exit MySQL

EXIT;

Step 3: Write PHP Code to Connect to MySQL Using Procedural Method

Here’s how you can connect to a MySQL database using the procedural method with mysqli:

<?php

$servername = “localhost”;

$username = “my_user”;

$password = “my_password”;

$database = “my_database”;

// Create connection

$conn = mysqli_connect($servername, $username, $password, $database);

// Check connection

if (!$conn) {

    die(“Connection failed: ” . mysqli_connect_error());

}

echo “Connected successfully”;

// Close the connection

mysqli_close($conn);

?>

Explanation of the Code

1. Connection Parameters:
   • $servername: The hostname of the MySQL server. For local development, this is usually localhost.
   • $username: The username to connect to the MySQL database.
   • $password: The password for the MySQL user.
   • $database: The name of the database you want to connect to.
2. mysqli_connect:
   • This function is used to open a new connection to the MySQL server.
   • It takes four parameters: the server name, the username, the password, and the database name.
3. mysqli_connect_error:
   • This function returns a string description of the last connect error, if any.
4. mysqli_close:
   • This function closes the previously opened database connection.