Warning: Undefined array key "artiste_id" in /home/httpd/vhosts/artgallery.ch/httpdocs/artiste_oeuvres_list.php on line 12

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 '' at line 1 in /home/httpd/vhosts/artgallery.ch/httpdocs/includes/class_artist.php:99
Stack trace:
#0 /home/httpd/vhosts/artgallery.ch/httpdocs/includes/class_artist.php(99): mysqli->query('SELECT * FROM A...')
#1 /home/httpd/vhosts/artgallery.ch/httpdocs/artiste_oeuvres_list.php(12): artist->set_userid(NULL)
#2 {main}
  thrown in /home/httpd/vhosts/artgallery.ch/httpdocs/includes/class_artist.php on line 99