[MySQL] 实现树形的遍历（关于多级菜单栏以及多级上下部门的查询问题）

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;

-- 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$$

-- 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$$

-- 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 ;

-- 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 ;

-- 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$$

-- 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 ;

-- 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$$

-- 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$$