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 'AND `delete` = 'N'' at line 1 in /ko8142/www/home/skin/default/content/layout/em_academy/book-summary.php:12
Stack trace:
#0 /ko8142/www/home/skin/default/content/layout/em_academy/book-summary.php(12): mysqli_query(Object(mysqli), 'SELECT     SUM(...')
#1 {main}
  thrown in /ko8142/www/home/skin/default/content/layout/em_academy/book-summary.php on line 12