yii去重

$criteria = new CDbCriteria;  

$criteria->alias = 't';  //table t，默认select='*';  

//一些public vars   

$criteria->select = 'id,parentid,name'; //代表了要查询的字段，默认select='*';    

$criteria->join = 'xxx'; //连接表    

$criteria->with = 'xxx'; //调用relations   

$criteria->with = array('accounts','varchar');  

$criteria->with  = array('teacher'=>  

    array(
        'select'=>'username,company_id',  

        'order'=>'teacher.username ASC'
        )  

);  

$criteria->limit = 10;    //取1条数据，如果小于0，则不作处理    

$criteria->offset = 1;   //两条合并起来，则表示 limit 10 offset 1,或者代表了。limit 1,10    

$criteria->order = 'xxx DESC,XXX ASC' ;//排序条件    

$criteria->group = 'group 条件';    

$criteria->having = 'having 条件 ';    

$criteria->distinct = FALSE; //是否唯一查询  

Article::model()->findAll($criteria);