Fatal error: Uncaught mysqli_sql_exception: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1 in /var/www/html/admin/includes/library_source.php:354
Stack trace:
#0 /var/www/html/admin/includes/library_source.php(354): mysqli_query()
#1 /var/www/html/admin/includes/tienda/cart/inc/functions.inc.php(225): consulta_bd()
#2 /var/www/html/pags/ficha.php(76): tieneDescuento()
#3 /var/www/html/index.php(52): include('...')
#4 {main}
thrown in /var/www/html/admin/includes/library_source.php on line 354