Connecting PHP to Databases: MySQL for Beginners

It is very important to connect to the MySQL database in PHP. The steps are as follows: Install the MySQL extension. Use the mysqli_connect() function to create a connection. The parameters include the host, user name, password and database name. Use the mysqli_connect_error() function to check whether the connection is successful. Practical case : Get all users, ensuring success by querying the database and checking the connection using the mysqli_connect_error() function. By understanding these steps and the examples provided, you can easily connect to a MySQL database in PHP.

Connecting PHP to a Database: MySQL for Beginners

Introduction

Connecting to a MySQL database in PHP is essential , because it allows your web application to interact with the backend database to store and retrieve data. In this article, we will show you how to connect to a MySQL database using PHP and provide a practical example to show it in action.

Steps

1. Install the MySQL extension

First, you need to install the MySQL extension on your server. For most Linux distributions, you can use the following command:

sudo apt-get install php-mysql

For Windows, you can download and install the PECL package from:

https://pecl.php.net /package/mysql

2. Create connection

To create a connection to the MySQL database, you can use the mysqli_connect() function. It takes the following parameters:

• $host: Hostname or IP address of the MySQL server
• $user: Database username
• $password: Database user password
• $database: Name of the database to be connected

$mysqli = new mysqli("localhost", "root", "password", "database_name");

3. Check the connection

After creating the connection, please use the mysqli_connect_error() function to check whether the connection is successful. If it returns null, it means the connection was successfully established.

if ($mysqli->connect_error) {
    die("无法连接到 MySQL: " . $mysqli->connect_error);
}

Practical Case: Get All Users

Now, let’s look at a practical case demonstrating how to get all users from a MySQL database using PHP.

$query = "SELECT * FROM users";
$result = $mysqli->query($query);

if ($result) {
    while ($row = $result->fetch_assoc()) {
        echo $row['name'] . "<br>";
    }
}

Conclusion

It is important to understand how to connect PHP to a MySQL database as this enables web applications to store and retrieve data. By following the steps in this article and understanding the practical examples provided, you can easily connect and use MySQL in your projects.

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