内容简介：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。
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：
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 |
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) ) ENGINE=INNODB DEFAULT CHARSET=utf8; 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
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 |
-- pro_cre_childlist DELIMITER 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_id=rootId; DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1; SET max_sp_recursion_depth=12; INSERT INTO tmpLst VALUES (NULL,rootId,nDepth); OPEN cur1; FETCH cur1 INTO b; WHILE done=0 DO CALL pro_cre_childlist(b,nDepth+1); 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
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 |
-- pro_cre_parentlist DELIMITER 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 id=rootId; DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1; SET max_sp_recursion_depth=12; INSERT INTO tmpLst VALUES (NULL,rootId,nDepth); OPEN cur1; FETCH cur1 INTO b; WHILE done=0 DO CALL pro_cre_parentlist(b,nDepth+1); 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
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 |
-- pro_cre_pathlist DELIMITER 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_depth=12; OPEN cur1; FETCH cur1 INTO parentid,pathstr; WHILE done=0 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
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 |
-- pro_cre_pnlist DELIMITER 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_depth=12; OPEN cur1; FETCH cur1 INTO parentid,pathstr; WHILE done=0 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
|
1 2 3 4 5 6 7 8 9 10 11 12 |
-- fn_tree_path DELIMITER 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 pathid=CAST(nid AS CHAR); CALL pro_cre_pathlist(nid,delimit,pathid); RETURN pathid; END |
2.6，调用函数输出name路径
|
1 2 3 4 5 6 7 8 9 10 11 12 |
-- 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
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 |
-- 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.id=channel.id ORDER BY tmpLst.sno; END |
2.8，调用过程输出父节点
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 |
-- pro_show_parentLst DELIMITER -- 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.id=channel.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：
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 |
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
|
1 2 3 4 5 6 7 8 9 10 11 12 13 |
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
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 |
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：
|
1 2 3 4 5 6 7 8 9 10 11 12 13 |
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：
|
1 2 3 4 5 6 7 8 9 10 11 |
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
|
1 2 3 4 5 6 7 |
CALL pro_show_parentLst(-1); mysql> CALL pro_show_parentLst(-1); Empty set (0.01 sec) Query OK, 0 rows affected (0.01 sec) mysql> |
3.7，显示“首页”的父节点
|
1 2 3 4 5 6 7 8 9 10 11 12 |
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-1
|
1 2 3 4 5 6 7 8 9 10 |
CALL 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
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 |
mysql> CALL 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) mysql> |
3.10，显示最低层节点“栏目简介”的父节点
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 |
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> |
参考网址：
http://jan.kneschke.de/projects/mysql/sp/sp_tree.sql
http://blog.csdn.net/ylqmf/article/details/5172901
原文出处： 黄杉
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持 码农网
猜你喜欢:
- 巧用 MyBatis 构建树形结构
- js 将线性数据转为树形
- 树形结构数据存储方案（五）：区间嵌套
- 树形结构数据存储方案（三）：闭包表
- 树形结构数据存储方案（二）： 物化路径
- PostgreSQL_树形结构的递归查询
本站部分资源来源于网络，本站转载出于传递更多信息之目的，版权归原作者或者来源机构所有，如转载稿涉及版权问题，请联系我们。
About Face 3
Alan Cooper、Robert Reimann、David Cronin / John Wiley & Sons / 2007-5-15 / GBP 28.99
* The return of the authoritative bestseller includes all new content relevant to the popularization of how About Face maintains its relevance to new Web technologies such as AJAX and mobile platforms......一起来看看 《About Face 3》 这本书的介绍吧!
