mysql 父类子类查询

查出子

DELIMITER $$

DROP FUNCTION IF EXISTS `getDeptChildList`$$

CREATE FUNCTION `getDeptChildList`(rootId INT) RETURNS varchar(1000) CHARSET utf8

    READS SQL DATA

    DETERMINISTIC

BEGIN 

       DECLARE pTemp VARCHAR(1000);  

       DECLARE cTemp VARCHAR(1000); 

      

       SET pTemp = '$';  

       SET cTemp =cast(rootId as CHAR);

      

       WHILE cTemp is not null DO  

         SET pTemp = concat(pTemp,',',cTemp);

         SELECT group_concat(id) INTO cTemp FROM roll_work_comment   

         WHERE FIND_IN_SET(mes_id,cTemp)>0; 

       END WHILE;  

       RETURN pTemp;  

     END;

 $$

DELIMITER ;

SELECT * FROM roll_work_comment  WHERE FIND_IN_SET(id,getDeptChildList(1)) ORDER BY id and mes_id;

查出父

SELECT T2.*

FROM ( 

    SELECT 

        @r AS _id, 

        (SELECT @r := mes_id FROM roll_work_comment WHERE id = _id) AS mes_id, 

        @l := @l + 1 AS lvl 

    FROM 

        (SELECT @r := 3, @l := 0) vars, 

        roll_work_comment h 

    WHERE @r <> 0) T1 

JOIN roll_work_comment T2 

ON T1._id = T2.id 

ORDER BY T1.lvl DESC