Fatal error: Uncaught exception 'PDOException' with message 'SQLSTATE[HY000]: General error: 1267 Illegal mix of collations (utf8_general_ci,IMPLICIT) and (gbk_chinese_ci,COERCIBLE) for operation '='' in E:\www\edusoho\vendor\doctrine\dbal\lib\Doctrine\DBAL\Connection.php:643 Stack trace: #0 E:\www\edusoho\vendor\doctrine\dbal\lib\Doctrine\DBAL\Connection.php(643): PDOStatement->execute(Array) #1 E:\www\edusoho\vendor\doctrine\dbal\lib\Doctrine\DBAL\Connection.php(381): Doctrine\DBAL\Connection->executeQuery('SELECT * FROM u...', Array) #2 E:\www\edusoho\src\Topxia\Service\User\Dao\Impl\UserDaoImpl.php(29): Doctrine\DBAL\Connection->fetchAssoc('SELECT * FROM u...', Array) #3 E:\www\edusoho\src\Topxia\Service\User\Impl\UserServiceImpl.php(237): Topxia\Service\User\Dao\Impl\UserDaoImpl->findUserByNickname('????????????') #4 E:\www\edusoho\src\Topxia\Service\User\Impl\UserServiceImpl.php(298): Topxia\Service\User\Impl\UserServiceImpl->isNicknameAvaliable('????????????') #5 E:\www\edusoho\web\install\install.php(261): Topxia\ in E:\www\edusoho\vendor\doctrine\dbal\lib\Doctrine\DBAL\DBALException.php on line 47