06:00:33 ERROR: SQLSTATE[HY000]: General error: 2006 MySQL server has gone away

The sql is: SELECT * FROM eps_file wHeRe objectType = 'book' AND objectID IN ('145') oRdEr bY `primary`, editor desc

in D:\xampp\htdocs\system\lib\dao\dao.class.php on line 596, last called by D:\xampp\htdocs\system\lib\dao\dao.class.php on line 713 through function query.
in D:\xampp\htdocs\system\framework\router.class.php on line 1698 when visiting book-read-103