How to use PHP to connect to phpmyadmin database (How to connect to mysql database with php)

How to connect to MySQL database with PHP? Create connection objects using MySQLi extension: php $conn = new mysqli(...); Ensure the database configuration information is accurate: php $servername, $username, $password, $dbname Check common errors: password error, database does not exist, port number problems, permission problems, coding problems Optimize performance: Use preprocessing statements to prevent SQL injection

PHP direct connection to MySQL: Stop taking turns!

Many newbies will ask, how to connect to phpMyAdmin with PHP? In fact, there is something wrong with this question itself. phpMyAdmin is just a database management tool. It does not store data by itself, so you have to deal with the database directly. So, the real question is: How to connect to MySQL database with PHP? After reading this article, you can use PHP to smoothly operate MySQL and no longer be confused by the "middleman" of phpMyAdmin.

Let’s talk about the basics first. MySQL is a relational database management system, and PHP is a server-side scripting language. They are connected through MySQLi extensions (or older mysql extensions, but are highly deprecated). MySQLi provides a safer and more efficient way to interact with the database. Remember, it's 2024 now, stop using outdated mysql extensions!

Now, let's directly upload the code to a simple and efficient connection example:

 <code class="php"><?php // 数据库配置信息，绝对不能硬编码到生产环境！ $servername = "localhost"; $username = "your_username"; $password = "your_password"; $dbname = "your_dbname"; // 创建连接$conn = new mysqli($servername, $username, $password, $dbname); // 检查连接if ($conn->connect_error) { die("连接失败: " . $conn->connect_error); } echo "连接成功！"; // 关闭连接-- 很重要！养成好习惯！ $conn->close(); ?></code>

This code is simple and the comments are clear. mysqli class provides everything you need to connect to a database. You have to replace the variables such as $servername , $username , $password , and $dbname with your own MySQL database configuration information. Remember, never write this information directly into the code, especially in production environments! They should be stored in the configuration file and included by include or require . This is related to the security of your database and cannot be careless!

Next, let’s talk about some possible pitfalls.

The first pit: the password is wrong. This is probably the most common mistake, double check your password case, special characters and make sure there are no errors. If you are using a root account, make sure that the password of the root account is set correctly and allows remote connections (if you are not connecting locally).

The second pit: the database does not exist. Make sure that the database name ( $dbname ) you specified does exist. You can check it with phpMyAdmin or other MySQL client tools.

The third pit: port number problem. By default, MySQL listens to port 3306, but in some cases it may be configured with different port numbers. You need to specify the port number in the connection string, for example: $conn = new mysqli($servername, $username, $password, $dbname, 3307); (if your port is 3307).

The fourth pit: permission issue. Your MySQL user may not have sufficient permissions to access the specified database or table. Check your user permissions to make sure it has sufficient read and write permissions.

The fifth pit: coding problem. If your database and PHP page use different character encodings, it may cause garbled code. It is recommended to use UTF-8 encoding in a unified manner. The encoding can be specified in the connection string: $conn = new mysqli($servername, $username, $password, $dbname); $conn->set_charset("utf8mb4"); Note that utf8mb4 is used here because it supports a wider character set, including emoji emoji.

Finally, regarding performance optimization, try to use prepared statements to prevent SQL injection vulnerabilities and improve execution efficiency. This part of the content is relatively advanced, so I won’t go into details here. You can search for relevant materials and learn it yourself. Remember, safety is always the first priority! When writing code, you should pursue concise, efficiency and safety like writing poetry, rather than pile up code!

The above is the detailed content of How to use PHP to connect to phpmyadmin database (How to connect to mysql database with php). For more information, please follow other related articles on the PHP Chinese website!