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前言 关于多级别菜单栏或者权限系统中部门上下级的树形遍历oracle中有connect by来实现mysql没有这样的便捷途径所以MySQL遍历数据表是我们经常会遇到的头痛问题下面通过存储过程来实现。1建立测试表和数据DROP TABLE IF EXISTS csdn.channel; CREATE TABLE csdn.channel ( id INT(11) NOT NULL AUTO_INCREMENT, cname VARCHAR(200) DEFAULT NULL, parent_id INT(11) DEFAULT NULL, PRIMARY KEY (id) ) ENGINEINNODB DEFAULT CHARSETutf8; INSERT INTO channel(id,cname,parent_id) VALUES (13,首页,-1), (14,TV580,-1), (15,生活580,-1), (16,左上幻灯片,13), (17,帮忙,14), (18,栏目简介,17); DROP TABLE IF EXISTS channel;2利用临时表和递归过程实现树的遍历mysql的UDF不能递归调用2.1从某节点向下遍历子节点递归生成临时表数据 -- pro_cre_childlistDELIMITER $$ DROP PROCEDURE IF EXISTS csdn.pro_cre_childlist$$ CREATE PROCEDURE csdn.pro_cre_childlist(IN rootId INT,IN nDepth INT) BEGIN DECLARE done INT DEFAULT 0; DECLARE b INT; DECLARE cur1 CURSOR FOR SELECT id FROM channel WHERE parent_idrootId; DECLARE CONTINUE HANDLER FOR NOT FOUND SET done 1; SET max_sp_recursion_depth12; INSERT INTO tmpLst VALUES (NULL,rootId,nDepth); OPEN cur1; FETCH cur1 INTO b; WHILE done0 DO CALL pro_cre_childlist(b,nDepth1); FETCH cur1 INTO b; END WHILE; CLOSE cur1; END$$ 2.2从某节点向上追溯根节点递归生成临时表数据 -- pro_cre_parentlistDELIMITER $$DROP PROCEDURE IF EXISTS csdn.pro_cre_parentlist$$ CREATE PROCEDURE csdn.pro_cre_parentlist(IN rootId INT,IN nDepth INT) BEGIN DECLARE done INT DEFAULT 0; DECLARE b INT; DECLARE cur1 CURSOR FOR SELECT parent_id FROM channel WHERE idrootId; DECLARE CONTINUE HANDLER FOR NOT FOUND SET done 1; SET max_sp_recursion_depth12; INSERT INTO tmpLst VALUES (NULL,rootId,nDepth); OPEN cur1; FETCH cur1 INTO b; WHILE done0 DO CALL pro_cre_parentlist(b,nDepth1); FETCH cur1 INTO b; END WHILE; CLOSE cur1; END$$ 2.3实现类似Oracle SYS_CONNECT_BY_PATH的功能递归过程输出某节点id路径 -- pro_cre_pathlistDELIMITER $$USE csdn$$DROP PROCEDURE IF EXISTS pro_cre_pathlist$$CREATE PROCEDURE pro_cre_pathlist(IN nid INT,IN delimit VARCHAR(10),INOUT pathstr VARCHAR(1000))BEGIN DECLARE done INT DEFAULT 0; DECLARE parentid INT DEFAULT 0; DECLARE cur1 CURSOR FOR SELECT t.parent_id,CONCAT(CAST(t.parent_id AS CHAR),delimit,pathstr) FROM channel AS t WHERE t.id nid; DECLARE CONTINUE HANDLER FOR NOT FOUND SET done 1; SET max_sp_recursion_depth12; OPEN cur1; FETCH cur1 INTO parentid,pathstr; WHILE done0 DO CALL pro_cre_pathlist(parentid,delimit,pathstr); FETCH cur1 INTO parentid,pathstr; END WHILE; CLOSE cur1; END$$DELIMITER ;2.4递归过程输出某节点name路径 -- pro_cre_pnlistDELIMITER $$USE csdn$$DROP PROCEDURE IF EXISTS pro_cre_pnlist$$CREATE PROCEDURE pro_cre_pnlist(IN nid INT,IN delimit VARCHAR(10),INOUT pathstr VARCHAR(1000))BEGIN DECLARE done INT DEFAULT 0; DECLARE parentid INT DEFAULT 0; DECLARE cur1 CURSOR FOR SELECT t.parent_id,CONCAT(t.cname,delimit,pathstr) FROM channel AS t WHERE t.id nid; DECLARE CONTINUE HANDLER FOR NOT FOUND SET done 1; SET max_sp_recursion_depth12; OPEN cur1; FETCH cur1 INTO parentid,pathstr; WHILE done0 DO CALL pro_cre_pnlist(parentid,delimit,pathstr); FETCH cur1 INTO parentid,pathstr; END WHILE; CLOSE cur1; END$$DELIMITER ;2.5调用函数输出id路径 -- fn_tree_pathDELIMITER $$ DROP FUNCTION IF EXISTS csdn.fn_tree_path$$ CREATE FUNCTION csdn.fn_tree_path(nid INT,delimit VARCHAR(10)) RETURNS VARCHAR(2000) CHARSET utf8 BEGIN DECLARE pathid VARCHAR(1000); SET pathidCAST(nid AS CHAR); CALL pro_cre_pathlist(nid,delimit,pathid); RETURN pathid; END$$ 2.6调用函数输出name路径 -- fn_tree_pathname-- 调用函数输出name路径 DELIMITER $$ DROP FUNCTION IF EXISTS csdn.fn_tree_pathname$$ CREATE FUNCTION csdn.fn_tree_pathname(nid INT,delimit VARCHAR(10)) RETURNS VARCHAR(2000) CHARSET utf8 BEGIN DECLARE pathid VARCHAR(1000); SET pathid; CALL pro_cre_pnlist(nid,delimit,pathid); RETURN pathid; END$$ DELIMITER ; 2.7调用过程输出子节点 -- pro_show_childLst DELIMITER $$-- 调用过程输出子节点 DROP PROCEDURE IF EXISTS pro_show_childLst$$ CREATE PROCEDURE pro_show_childLst(IN rootId INT) BEGIN DROP TEMPORARY TABLE IF EXISTS tmpLst; CREATE TEMPORARY TABLE IF NOT EXISTS tmpLst (sno INT PRIMARY KEY AUTO_INCREMENT,id INT,depth INT); CALL pro_cre_childlist(rootId,0); SELECT channel.id,CONCAT(SPACE(tmpLst.depth*2),--,channel.cname) NAME,channel.parent_id,tmpLst.depth,fn_tree_path(channel.id,/) path,fn_tree_pathname(channel.id,/) pathname FROM tmpLst,channel WHERE tmpLst.idchannel.id ORDER BY tmpLst.sno; END$$ 2.8调用过程输出父节点 -- pro_show_parentLstDELIMITER $$-- 调用过程输出父节点 DROP PROCEDURE IF EXISTS pro_show_parentLst$$ CREATE PROCEDURE pro_show_parentLst(IN rootId INT) BEGIN DROP TEMPORARY TABLE IF EXISTS tmpLst; CREATE TEMPORARY TABLE IF NOT EXISTS tmpLst (sno INT PRIMARY KEY AUTO_INCREMENT,id INT,depth INT); CALL pro_cre_parentlist(rootId,0); SELECT channel.id,CONCAT(SPACE(tmpLst.depth*2),--,channel.cname) NAME,channel.parent_id,tmpLst.depth,fn_tree_path(channel.id,/) path,fn_tree_pathname(channel.id,/) pathname FROM tmpLst,channel WHERE tmpLst.idchannel.id ORDER BY tmpLst.sno; END$$ 3开始测试3.1从根节点开始显示显示子节点集合 mysql CALL pro_show_childLst(-1); --------------------------------------------------------------------------------------| id | NAME | parent_id | depth | path | pathname |--------------------------------------------------------------------------------------| 13 | --首页 | -1 | 1 | -1/13 | 首页/ || 16 | --左上幻灯片 | 13 | 2 | -1/13/16 | 首页/左上幻灯片/ || 14 | --TV580 | -1 | 1 | -1/14 | TV580/ || 17 | --帮忙 | 14 | 2 | -1/14/17 | TV580/帮忙/ || 18 | --栏目简介 | 17 | 3 | -1/14/17/18 | TV580/帮忙/栏目简介/ || 15 | --生活580 | -1 | 1 | -1/15 | 生活580/ |--------------------------------------------------------------------------------------6 rows in set (0.05 sec)Query OK, 0 rows affected (0.05 sec)3.2显示首页下面的子节点CALL pro_show_childLst(13); mysql CALL pro_show_childLst(13); ------------------------------------------------------------------------------| id | NAME | parent_id | depth | path | pathname |------------------------------------------------------------------------------| 13 | --首页 | -1 | 0 | -1/13 | 首页/ || 16 | --左上幻灯片 | 13 | 1 | -1/13/16 | 首页/左上幻灯片/ |------------------------------------------------------------------------------2 rows in set (0.02 sec)Query OK, 0 rows affected (0.02 sec)mysql 3.3显示TV580下面的所有子节点CALL pro_show_childLst(14); mysql CALL pro_show_childLst(14); -----------------------------------------------------------------------------------| id | NAME | parent_id | depth | path | pathname |-----------------------------------------------------------------------------------| 14 | --TV580 | -1 | 0 | -1/14 | TV580/ || 17 | --帮忙 | 14 | 1 | -1/14/17 | TV580/帮忙/ || 18 | --栏目简介 | 17 | 2 | -1/14/17/18 | TV580/帮忙/栏目简介/ |-----------------------------------------------------------------------------------3 rows in set (0.02 sec)Query OK, 0 rows affected (0.02 sec)mysql 3.4“帮忙”节点有一个子节点显示出来CALL pro_show_childLst(17); mysql CALL pro_show_childLst(17); ---------------------------------------------------------------------------------| id | NAME | parent_id | depth | path | pathname |---------------------------------------------------------------------------------| 17 | --帮忙 | 14 | 0 | -1/14/17 | TV580/帮忙/ || 18 | --栏目简介 | 17 | 1 | -1/14/17/18 | TV580/帮忙/栏目简介/ |---------------------------------------------------------------------------------2 rows in set (0.03 sec)Query OK, 0 rows affected (0.03 sec)mysql 3.5“栏目简介”没有子节点所以只显示最终节点mysql CALL pro_show_childLst(18); -------------------------------------------------------------------------------| id | NAME | parent_id | depth | path | pathname |-------------------------------------------------------------------------------| 18 | --栏目简介 | 17 | 0 | -1/14/17/18 | TV580/帮忙/栏目简介/ |-------------------------------------------------------------------------------1 row in set (0.36 sec)Query OK, 0 rows affected (0.36 sec)mysql 3.6显示根节点的父节点 CALL pro_show_parentLst(-1); mysql CALL pro_show_parentLst(-1);Empty set (0.01 sec)Query OK, 0 rows affected (0.01 sec)mysql3.7显示“首页”的父节点CALL pro_show_parentLst(13); mysql CALL pro_show_parentLst(13); -------------------------------------------------| id | NAME | parent_id | depth | path | pathname |-------------------------------------------------| 13 | --首页 | -1 | 0 | -1/13 | 首页/ |-------------------------------------------------1 row in set (0.02 sec)Query OK, 0 rows affected (0.02 sec)mysql 3.8显示“TV580”的父节点parent_id为-1CALL pro_show_parentLst(14); mysql CALL pro_show_parentLst(14); ------------------------------------------------| id | NAME | parent_id | depth | path | pathname |------------------------------------------------| 14 | --TV580 | -1 | 0 | -1/14 | TV580/ |------------------------------------------------1 row in set (0.02 sec)Query OK, 0 rows affected (0.02 sec)3.9显示“帮忙”节点的父节点mysqlCALL pro_show_parentLst(17); mysql CALL pro_show_parentLst(17); ----------------------------------------------------------| id | NAME | parent_id | depth | path | pathname |----------------------------------------------------------| 17 | --帮忙 | 14 | 0 | -1/14/17 | TV580/帮忙/ || 14 | --TV580 | -1 | 1 | -1/14 | TV580/ |----------------------------------------------------------2 rows in set (0.02 sec)Query OK, 0 rows affected (0.02 sec)mysql3.10显示最低层节点“栏目简介”的父节点CALL pro_show_parentLst(18); mysql CALL pro_show_parentLst(18); -------------------------------------------------------------------------------| id | NAME | parent_id | depth | path | pathname |-------------------------------------------------------------------------------| 18 | --栏目简介 | 17 | 0 | -1/14/17/18 | TV580/帮忙/栏目简介/ || 17 | --帮忙 | 14 | 1 | -1/14/17 | TV580/帮忙/ || 14 | --TV580 | -1 | 2 | -1/14 | TV580/ |-------------------------------------------------------------------------------3 rows in set (0.02 sec)Query OK, 0 rows affected (0.02 sec)mysql 原文http://blog.csdn.net/mchdba/article/details/39277301参考网址 http://jan.kneschke.de/projects/mysql/sp/sp_tree.sqlhttp://blog.csdn.net/ylqmf/article/details/5172901
