Solution to PHP Fatal error: Call to undefined function mysql_pconnect()

PHP is a very popular open source programming language that is widely used in web application development. However, in the process of developing web applications using PHP, you sometimes encounter the following error message:

PHP Fatal error: Call to undefined function mysql_pconnect()

This error message means that A fatal error occurred because PHP could not find the mysql_pconnect() function. This usually means that PHP has not installed or configured the MySQL extension library correctly. If you encounter this problem, don’t worry, this article will introduce you to several possible solutions.

1. Confirm that the MySQL extension library has been loaded correctly

You need to confirm that you have correctly installed and configured the MySQL extension library. You can look for the following line in the php.ini file:

extension=php_mysql.dll

If this line is not found, add it to the configuration file and restart your web server.

2. Check the MySQL extension library version

If you have confirmed that the MySQL extension library is correctly installed and configured, please check its version. Make sure your MySQL extension library version is compatible with your PHP version. If it is not compatible, you need to upgrade the MySQL extension library or downgrade the PHP version.

3. Enable MySQL extension library

Sometimes, even when the MySQL extension library is installed and configured correctly, your PHP script may still be unable to find the mysql_pconnect() function . This may be because the MySQL extension library is not enabled. In php.ini you need to find the following line:

;extension=mysql.so

Change it to:

extension=mysql.so

Or if you are running PHP under Windows:

extension=php_mysql.dll

Then restart your web server.

4. Use mysqli to connect to MySQL

If you cannot solve the problem, you can try to use the mysqli extension to connect to MySQL. The mysqli extension is an extension for PHP that provides better performance and more functionality. You need to replace the original mysql_xx() function with the mysqli_xx() function, such as:

$mysqli = new mysqli('host', 'username', 'password', 'database');

If your PHP version is lower than 5.0, you need to use the mysql_connect() function in the MySQLi extension library, such as:

$mysqli = mysqli_connect('host', 'username', 'password' , 'database');

Summary

Here, we provide several methods to solve PHP Fatal error: Call to undefined function mysql_pconnect(). If you still can't solve the problem, make sure you have correctly installed and configured the MySQL extension library and a compatible PHP version. In the meantime, you can try to use mysqli to connect to MySQL to solve the problem.

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