Cannot execute queries while other unbuffered ....

: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 /www/KFC/Components/libs/mypdo/mypdo.class.php on line 54

在程序中将 $db->exec($sql) 改成 $db->execute($sql) 解决问题


原因进一步研究中


相关连接:
http://usphp.com/manual/en/function.PDO-exec.php