用户登陆报错

错误信息:
Fatal error: Uncaught exception 'Zend_Auth_Adapter_Exception' with message 'The supplied parameters to Zend_Auth_Adapter_DbTable failed to produce a valid sql statement, please check table and column names for validity.' in /usr/local/apache2/htdocs/library/Zend/Auth/Adapter/DbTable.php:323 Stack trace: #0 /usr/local/apache2/htdocs/library/Zend/Auth.php(118): Zend_Auth_Adapter_DbTable->authenticate() #1 /usr/local/apache2/htdocs/modules/My/Auth.php(31): Zend_Auth->authenticate(Object(Zend_Auth_Adapter_DbTable)) #2 /usr/local/apache2/htdocs/default/controllers/AuthController.php(28): My_Auth->login('liming', '123123') #3 /usr/local/apache2/htdocs/library/Zend/Controller/Action.php(497): AuthController->loginAction() #4 /usr/local/apache2/htdocs/library/Zend/Controller/Dispatcher/Standard.php(237): Zend_Controller_Action->dispatch('loginAction') #5 /usr/local/apache2/htdocs/library/Zend/Controller/Front.php(911): Zend_Controller_Dispatcher_Standard->dispatch(Object(Zend_Controller_Request_Http), Object(Zend_Controller_Resp in /usr/local/apache2/htdocs/library/Zend/Auth/Adapter/DbTable.php on line 323
这事什么问题啊?我因该怎么解决啊,求求各位高人指点一下吧