这个得益于Mysql允许在SQL语句内使用@变量。
以下是示例代码。
创建表格CREATE TABLE `lf_ctrl_trade` ( `TRADEID` int , -- 节点ID `nodename` varchar (60), -- 节点名称 `PARENTID` int -- 节点父ID); 方案一: SELECT TRADEID AS ID,PARENTID AS 父ID ,levels AS 父到子之间级数, paths AS 父到子路径 FROM ( SELECT TRADEID,PARENTID, @le:= IF (PARENTID = 0 ,0, IF( LOCATE( CONCAT('|',PARENTID,':'),@pathlevel) > 0 , SUBSTRING_INDEX( SUBSTRING_INDEX(@pathlevel,CONCAT('|',PARENTID,':'),-1),'|',1) +1 ,@le+1) ) levels , @pathlevel:= CONCAT(@pathlevel,'|',TRADEID,':', @le ,'|') pathlevel , @pathnodes:= IF( PARENTID =0,',0', CONCAT_WS(',', IF( LOCATE( CONCAT('|',PARENTID,':'),@pathall) > 0 , SUBSTRING_INDEX( SUBSTRING_INDEX(@pathall,CONCAT('|',PARENTID,':'),-1),'|',1) ,@pathnodes ) ,PARENTID ) )paths ,@pathall:=CONCAT(@pathall,'|',TRADEID,':', @pathnodes ,'|') pathall FROM lf_ctrl_trade, (SELECT @le:=0,@pathlevel:='', @pathall:='',@pathnodes:='') vv ORDER BY PARENTID,TRADEID ) srcORDER BY TRADEID方案二:创建函数DROP FUNCTION IF EXISTS queryChildrenTrade;CREATE FUNCTION `queryChildrenTrade` (myid INT)RETURNS VARCHAR(4000)BEGINDECLARE sTemp VARCHAR(4000);DECLARE sTempChd VARCHAR(4000); SET sTemp = '$';SET sTempChd = cast(myid as char); WHILE sTempChd is not NULL DOSET sTemp = CONCAT(sTemp,',',sTempChd);SELECT group_concat(TRADEID) INTO sTempChd FROM lf_ctrl_trade where FIND_IN_SET(PARENTID,sTempChd)>0;END WHILE;return sTemp;END;如何查询:select * from lf_ctrl_trade where FIND_IN_SET(TRADEID, queryChildrenTrade(3000))
欢迎分享,转载请注明来源:内存溢出
评论列表(0条)