问Zend Db选择add subquery to FROM part

EN

SELECT COUNT(row_1) AS count_row FROM (SELECT row,row2,... FROM table WHERE row= ...) AS temp WHERE row = 0)

$oSubSelect = 
                $this->select()
                     ->setIntegrityCheck(false)   
                     ->from('table',
                             array(
                                 'row_id'
                                 )
                             )
                     ->where(PRFX.'table.id = '.PRFX.'table2.id')

                     ->from(PRFX.'table2',array('row','row2'));
    $this->select(false)
         ->setIntegrityCheck(false)
         ->from(new Zend_Db_Expr($oSubSelect).' AS temp',
                array(
                    'COUNT(row_id) AS row_count',
                    )
                );