SQLSTATE[HY000]: General error: 2013 Lost connection to MySQL server during query

FILE: /data1/www/htdocs/898/yicir/3/ThinkPHP/Library/Think/Db/Driver.class.php 　LINE: 169

#0 /data1/www/htdocs/898/yicir/3/ThinkPHP/Library/Think/Db/Driver.class.php(169): PDOStatement->execute()
#1 /data1/www/htdocs/898/yicir/3/ThinkPHP/Library/Think/Model.class.php(1362): Think\Db\Driver->query('select a.Course...')
#2 /data1/www/htdocs/898/yicir/3/Application/Common/Model/BaseModel.class.php(125): Think\Model->query('select a.Course...')
#3 /data1/www/htdocs/898/yicir/3/Application/Course/Model/CourseModel.class.php(178): Common\Model\BaseModel->queryList('select a.Course...')
#4 /data1/www/htdocs/898/yicir/3/Application/Course/Model/CourseModel.class.php(194): Course\Model\CourseModel->getLessonList('latinitasmagnae...', 0)
#5 /data1/www/htdocs/898/yicir/3/Application/Course/Controller/LessonController.class.php(223): Course\Model\CourseModel->getCourseByRowId(46, true)
#6 /data1/www/htdocs/898/yicir/3/Application/Course/Controller/LessonController.class.php(15): Course\Controller\LessonController->displayLessonPage(772, 2)
#7 /data1/www/htdocs/898/yicir/3/ThinkPHP/Library/Think/Controller.class.php(165): Course\Controller\LessonController->_empty('772', '')
#8 [internal function]: Think\Controller->__call('772', '')
#9 /data1/www/htdocs/898/yicir/3/ThinkPHP/Library/Think/App.class.php(180): ReflectionMethod->invokeArgs(Object(Course\Controller\LessonController), Array)
#10 /data1/www/htdocs/898/yicir/3/ThinkPHP/Library/Think/App.class.php(202): Think\App::exec()
#11 /data1/www/htdocs/898/yicir/3/ThinkPHP/Library/Think/Think.class.php(120): Think\App::run()
#12 /data1/www/htdocs/898/yicir/3/ThinkPHP/ThinkPHP.php(97): Think\Think::start()
#13 /data1/www/htdocs/898/yicir/3/index.php(25): require('/data1/www/htdo...')
#14 {main}