Fatal error: Uncaught Error: Call to undefined function mysql_connect() in /opt/wordpress/wp-includes/wp-db.php:1564
Stack trace:
#0 /opt/wordpress/wp-includes/wp-db.php(592): wpdb->db_connect()
#1 /opt/wordpress/wp-includes/load.php(404): wpdb->__construct('root', '', 'wordpress', '127.0.0.1')
#2 /opt/wordpress/wp-settings.php(106): require_wp_db()
#3 /opt/wordpress/wp-config.php(89): require_once('/opt/wordpress/...')
#4 /opt/wordpress/wp-load.php(37): require_once('/opt/wordpress/...')
#5 /opt/wordpress/wp-blog-header.php(13): require_once('/opt/wordpress/...')
#6 /opt/wordpress/index.php(17): require('/opt/wordpress/...')
#7 {main}
thrown in /opt/wordpress/wp-includes/wp-db.php on line 1564