This is a php single function that connects to mysql database by specifying in the called function "pdo" or "mysqli"
This function is very easy to use.
In the index.php file, we gave an example of an html form submit that takes action of either pdo_register.php or mysqli_register.php that calls the function to connect the database. You can read more about the function in this article http://blog.m3tech.com.ng/posts/@Obrain157452018420191123-40/php-single-function-to-connect-the-database-using-either-pdo-or-mysqli