Source
File: wp-includes/load.php
function wp_check_php_mysql_versions() {
global $required_php_version, $wp_version;
$php_version = phpversion();
if ( version_compare( $required_php_version, $php_version, '>' ) ) {
$protocol = wp_get_server_protocol();
header( sprintf( '%s 500 Internal Server Error', $protocol ), true, 500 );
header( 'Content-Type: text/html; charset=utf-8' );
printf( 'Your server is running PHP version %1$s but WordPress %2$s requires at least %3$s.', $php_version, $wp_version, $required_php_version );
exit( 1 );
}
if ( ! extension_loaded( 'mysql' ) && ! extension_loaded( 'mysqli' ) && ! extension_loaded( 'mysqlnd' ) && ! file_exists( WP_CONTENT_DIR . '/db.php' ) ) {
require_once ABSPATH . WPINC . '/functions.php';
wp_load_translations_early();
$args = array(
'exit' => false,
'code' => 'mysql_not_found',
);
wp_die(
__( 'Your PHP installation appears to be missing the MySQL extension which is required by WordPress.' ),
__( 'Requirements Not Met' ),
$args
);
exit( 1 );
}
}