萬盛學電腦網

浏覽器 windows 10 wps office 殺毒軟件 數據庫 excel教程 文件管理 word教程 網頁制作 裝機必備軟件 linux教程

 萬盛學電腦網 >> 數據庫 >> mysql教程 >> MySQL 實現樹形的遍歷的詳解

MySQL 實現樹形的遍歷的詳解

下面我們來看一篇關於MySQL 實現樹形的遍歷的例子，希望這篇文章能夠幫助到各位朋友，具體的步驟細節如下文介紹。

前言：

關於多級別菜單欄或者權限系統中部門上下級的樹形遍歷，oracle中有connect by來實現，mysql沒有這樣的便捷途徑，所以MySQL遍歷數據表是我們經常會遇到的頭痛問題，下面通過存儲過程來實現。

1，建立測試表和數據：

MySQL

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,'首頁',-1),  
       (14,'TV580',-1),  
       (15,'生活580',-1),  
       (16,'左上幻燈片',13),  
       (17,'幫忙',14),  
       (18,'欄目簡介',17); 
DROP TABLE IF EXISTS channel;


2，利用臨時表和遞歸過程實現樹的遍歷（mysql的UDF不能遞歸調用）：
2.1，從某節點向下遍歷子節點，遞歸生成臨時表數據

MySQL

-- 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，從某節點向上追溯根節點，遞歸生成臨時表數據

MySQL

-- 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，實現類似Oracle SYS_CONNECT_BY_PATH的功能，遞歸過程輸出某節點id路徑

MySQL

-- 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，遞歸過程輸出某節點name路徑

MySQL

-- 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，調用函數輸出id路徑

MySQL

-- 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，調用函數輸出name路徑

MySQL

-- fn_tree_pathname
-- 調用函數輸出name路徑  
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，調用過程輸出子節點

MySQL

-- pro_show_childLst 
DELIMITER
-- 調用過程輸出子節點  
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，調用過程輸出父節點

MySQL

-- pro_show_parentLst
DELIMITER
-- 調用過程輸出父節點  
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，開始測試
：

3.1，從根節點開始顯示，顯示子節點集合：

MySQL

mysql> CALL pro_show_childLst(-1);
+----+-----------------------+-----------+-------+-------------+----------------------------+
| id | NAME                  | parent_id | depth | path        | pathname                   |
+----+-----------------------+-----------+-------+-------------+----------------------------+
| 13 |   --首頁              |        -1 |     1 | -1/13       | 首頁/                      |
| 16 |     --左上幻燈片      |        13 |     2 | -1/13/16    | 首頁/左上幻燈片/           |
| 14 |   --TV580             |        -1 |     1 | -1/14       | TV580/                     |
| 17 |     --幫忙            |        14 |     2 | -1/14/17    | TV580/幫忙/                |
| 18 |       --欄目簡介      |        17 |     3 | -1/14/17/18 | TV580/幫忙/欄目簡介/       |
| 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，顯示首頁下面的子節點

MySQL

CALL pro_show_childLst(13);
mysql> CALL pro_show_childLst(13);
+----+---------------------+-----------+-------+----------+-------------------------+
| id | NAME                | parent_id | depth | path     | pathname                |
+----+---------------------+-----------+-------+----------+-------------------------+
| 13 | --首頁              |        -1 |     0 | -1/13    | 首頁/                   |
| 16 |   --左上幻燈片      |        13 |     1 | -1/13/16 | 首頁/左上幻燈片/        |
+----+---------------------+-----------+-------+----------+-------------------------+
2 rows in set (0.02 sec)

Query OK, 0 rows affected (0.02 sec)

mysql>


3.3，顯示TV580下面的所有子節點

MySQL

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 |   --幫忙           |        14 |     1 | -1/14/17    | TV580/幫忙/                |
| 18 |     --欄目簡介     |        17 |     2 | -1/14/17/18 | TV580/幫忙/欄目簡介/       |
+----+--------------------+-----------+-------+-------------+----------------------------+
3 rows in set (0.02 sec)

Query OK, 0 rows affected (0.02 sec)

mysql>

 

3.4，“幫忙”節點有一個子節點，顯示出來：

MySQL

CALL pro_show_childLst(17);
mysql> CALL pro_show_childLst(17);
+----+------------------+-----------+-------+-------------+----------------------------+
| id | NAME             | parent_id | depth | path        | pathname                   |
+----+------------------+-----------+-------+-------------+----------------------------+
| 17 | --幫忙           |        14 |     0 | -1/14/17    | TV580/幫忙/                |
| 18 |   --欄目簡介     |        17 |     1 | -1/14/17/18 | TV580/幫忙/欄目簡介/       |
+----+------------------+-----------+-------+-------------+----------------------------+
2 rows in set (0.03 sec)

Query OK, 0 rows affected (0.03 sec)

mysql>

 

3.5，“欄目簡介”沒有子節點，所以只顯示最終節點：

MySQL

mysql> CALL pro_show_childLst(18);
+----+----------------+-----------+-------+-------------+----------------------------+
| id | NAME           | parent_id | depth | path        | pathname                   |
+----+----------------+-----------+-------+-------------+----------------------------+
| 18 | --欄目簡介     |        17 |     0 | -1/14/17/18 | TV580/幫忙/欄目簡介/       |
+----+----------------+-----------+-------+-------------+----------------------------+
1 row in set (0.36 sec)

Query OK, 0 rows affected (0.36 sec)

mysql>


3.6，顯示根節點的父節點

MySQL

CALL pro_show_parentLst(-1);
mysql> CALL pro_show_parentLst(-1);
Empty set (0.01 sec)

Query OK, 0 rows affected (0.01 sec)

 

3.7，顯示“首頁”的父節點

MySQL

CALL pro_show_parentLst(13);
mysql> CALL pro_show_parentLst(13);
+----+----------+-----------+-------+-------+----------+
| id | NAME     | parent_id | depth | path  | pathname |
+----+----------+-----------+-------+-------+----------+
| 13 | --首頁   |        -1 |     0 | -1/13 | 首頁/    |
+----+----------+-----------+-------+-------+----------+
1 row in set (0.02 sec)

Query OK, 0 rows affected (0.02 sec)

mysql>

 

3.8，顯示“TV580”的父節點，parent_id為-1

MySQL

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，顯示“幫忙”節點的父節點

MySQL

mysql>
CALL pro_show_parentLst(17);
mysql> CALL pro_show_parentLst(17);
+----+-----------+-----------+-------+----------+---------------+
| id | NAME      | parent_id | depth | path     | pathname      |
+----+-----------+-----------+-------+----------+---------------+
| 17 | --幫忙    |        14 |     0 | -1/14/17 | TV580/幫忙/   |
| 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，顯示最低層節點“欄目簡介”的父節點

MySQL

CALL pro_show_parentLst(18);
mysql> CALL pro_show_parentLst(18);
+----+----------------+-----------+-------+-------------+----------------------------+
| id | NAME           | parent_id | depth | path        | pathname                   |
+----+----------------+-----------+-------+-------------+----------------------------+
| 18 | --欄目簡介     |        17 |     0 | -1/14/17/18 | TV580/幫忙/欄目簡介/       |
| 17 |   --幫忙       |        14 |     1 | -1/14/17    | TV580/幫忙/                |
| 14 |     --TV580    |        -1 |     2 | -1/14       | TV580/                     |
+----+----------------+-----------+-------+-------------+----------------------------+
3 rows in set (0.02 sec)

Query OK, 0 rows affected (0.02 sec)

 

mysql教程排行

程序編程推薦

熱門文章

 [ps文字教程]PhotoShop制作透明玻璃質感金…
 [javascript]Java多線程的同步示例及對象鎖機制
 [安全資訊防護]免費Windows防火牆推薦
 [Html5]html表格跨列的方法
 [mysql教程]兩mysql數據庫同步實現異步備份方…
 [windows 8技巧]Win8打開設備管理器的步驟

相關文章

圖片文章

從業務視角看交互設計師的價值

 　　最近和組裡的設計師review近期工作進展時，發現了不少問題。想起設計新人一臉無辜和迷茫的表情，…

mac版safari浏覽記錄怎麼刪除？

 　　mac版safari浏覽記錄怎麼刪除？        有…

國外免費導航菜單PSD模板

導航菜單是一個網站最為重要的部分之一，設計精良的導航菜單可在第一時間吸引用戶，給用戶准確直觀的信息傳達，引導用戶…

網頁設計：20個值得關注的作品集網站案例

作品是展示個人才能的最佳方式，像設計，攝影這些創造性的職業特別需要有個人作品集網站，讓你以個性方式展示自我並呈現…

萬盛學電腦網 | 設為首頁 | 加入收藏

copyright © 萬盛學電腦網 all rights reserved