无限级的过程
上下级会员关系通过id和pid确定。
例如:a>b>c>d>e>f>g...
就是a的下级是b,b的下级是c,c的下级是d....(有点类似传*销模式?无视掉)
需求,通过用户g查出所有的上级,则要查到f.e.d.c.b.a这些用户id
方可给这些上级发送通知。
我们最重要的是取出上级id然后就好办多了。
首先说明几个值,user_id 为用户表中的用户id,parent_id为表中用户的上级id。
示例一条基本的查询父级idSQL。
SELECT parent_id FROM cx_user WHERE user_id = 10;##查询user_id为10的上级id
不说废话了,直接进入中心。
打开MySQL开始写存储过程。
DROP PROCEDURE IF EXISTS `getpid`;CREATE DEFINER = `root`@`localhost` PROCEDURE `getpid`(IN `id` int)BEGINSET @pid:=id;#id为查询的参数 即当前用户idSET @pidarr:=''; #查询到的上级数组字符串recursion:WHILE @pid!=0 DO SELECT parent_id INTO @pid from cx_users WHERE user_id = @pid;#这里是你查询的SQL语句 @pid是动态id IF @pid=0 THEN #到0即结束 LEAVE recursion; END IF; IF LOCATE(@pid,@pidarr)>0 THEN #防止出现上下级关系混乱 LEAVE recursion; END IF; set @pidarr = concat(@pidarr,@pid); set @pidarr = concat(@pidarr,','); END WHILE recursion;SELECT @pidarr AS pidarr;END;
存储过程执行结果,拿图吓唬吓唬你。
PHP端demo
$sql = "CALL getpid(104);";$pidstr = mysql_query($sql);//换成你项目中执行MySQL的函数即可 然后取出 pidarr的值到$pidstr$pidstr = rtrim($pidstr,',');//剔除最右侧多余英文逗号$pidarr = explode(',',$pidstr);//到数组//以下随意 #ncSJI$@CO3N#@329090*(@@()$u)@j(@(h(@jn9NCD9823N892

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