Fatal error: Uncaught PDOException: SQLSTATE[40001]: Serialization failure: 1213 Deadlock found when trying to get lock; try restarting transaction in /home/instit11/public_html/online/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOStatement.php:117 Stack trace: #0 /home/instit11/public_html/online/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOStatement.php(117): PDOStatement->execute(Array) #1 /home/instit11/public_html/online/vendor/doctrine/dbal/lib/Doctrine/DBAL/Statement.php(179): Doctrine\DBAL\Driver\PDOStatement->execute(Array) #2 /home/instit11/public_html/online/main/inc/lib/database.lib.php(529): Doctrine\DBAL\Statement->execute(Array) #3 /home/instit11/public_html/online/main/inc/lib/course.lib.php(5091): Database::update('track_course_ra...', Array, Array) #4 /home/instit11/public_html/online/main/inc/lib/events.lib.php(2238): CourseManager::update_course_ranking('71', 0, 1, NULL, true, false) #5 /home/instit11/public_html/online/main/inc/local.inc.php(1223): Event::eventCourseLogin(71, 2, 0) #6 /home/ins in /home/instit11/public_html/online/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/AbstractMySQLDriver.php on line 51