MySQL递归查询树状表的子节点、父节点_MySQL

简介：mysql5.0.94版本，该版本以及较高级的版本（5.5、6等等）尚未支持循环递归查询，和sqlserver、oracle相比，mysql难于在树状表中层层遍历的子节点。本程序重点参考了下面的资料，写了两个sql存储过程，子节点查询算是照搬了，父节点查询是逆思维弄的。

资料参考：http://blog.csdn.net/ACMAIN_CHM/article/details/4142971#comments

表结构和表数据就不公示了，查询的表user_role，主键是id，每条记录有parentid字段（对应该记录的父节点，当然，一个父节点自然会有一个以上的子节点嘛）

CREATE FUNCTION `getChildList`(rootId INT)    RETURNS varchar(1000)    BEGIN      DECLARE sChildList VARCHAR(1000);      DECLARE sChildTemp VARCHAR(1000);      SET sChildTemp =cast(rootId as CHAR);      WHILE sChildTemp is not null DO        IF (sChildList is not null) THEN          SET sChildList = concat(sChildList,',',sChildTemp);	ELSE	  SET sChildList = concat(sChildTemp);	END IF;        SELECT group_concat(id) INTO sChildTemp FROM user_role where FIND_IN_SET(parentid,sChildTemp)>0;      END WHILE;      RETURN sChildList;    END;/*获取子节点*//*调用: 1、select getChildList(0) id; 2、select * 5From user_role where FIND_IN_SET(id, getChildList(2));*/CREATE FUNCTION `getParentList`(rootId INT)    RETURNS varchar(1000)    BEGIN      DECLARE sParentList varchar(1000);      DECLARE sParentTemp varchar(1000);      SET sParentTemp =cast(rootId as CHAR);      WHILE sParentTemp is not null DO	IF (sParentList is not null) THEN         SET sParentList = concat(sParentTemp,',',sParentList);	ELSE	 SET sParentList = concat(sParentTemp);	END IF;        SELECT group_concat(parentid) INTO sParentTemp FROM user_role where FIND_IN_SET(id,sParentTemp)>0;      END WHILE;      RETURN sParentList;    END;/*获取父节点*//*调用: 1、select getParentList(6) id; 2、select * From user_role where FIND_IN_SET(id, getParentList(2));*/