Fatal error: Uncaught mysqli_sql_exception: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '-4' at line 1 in /home/u810780627/domains/centroubuntu.net/public_html/educational/workshops/index.php:33 Stack trace: #0 /home/u810780627/domains/centroubuntu.net/public_html/educational/workshops/index.php(33): mysqli->query() #1 {main} thrown in /home/u810780627/domains/centroubuntu.net/public_html/educational/workshops/index.php on line 33