```
2017-07-03 10:58:50 pid:17822 PDOException: SQL:select * from config_rand_name group by `type` SQLSTATE: General error: 2014 Cannot execute queries while other unbuffered queries are active. Consider using PDOStatement::fetchAll(). Alternatively, if your code is only ever going to run against mysql, you may enable query buffering by setting the PDO::MYSQL_ATTR_USE_BUFFERED_QUERY attribute. in /root/workerman-win/vendor/workerman/gateway-worker/src/Lib/DbConnection.php:1766
```
请问这个是什么问题 要怎么解决呢