MySQL存储过程实现Oracle邻接模型树形处理的方法实例

-- Table country_relation.
insert into country_relation (id,parentid) values (0,NULL);
insert into country_relation (id,parentid) values (2,0);
insert into country_relation (id,parentid) values (3,0);
insert into country_relation (id,parentid) values (4,0);
insert into country_relation (id,parentid) values (5,0);
insert into country_relation (id,parentid) values (6,0);
insert into country_relation (id,parentid) values (7,0);
insert into country_relation (id,parentid) values (8,2);
insert into country_relation (id,parentid) values (9,2);
insert into country_relation (id,parentid) values (10,2);
insert into country_relation (id,parentid) values (11,2);
insert into country_relation (id,parentid) values (12,11);
insert into country_relation (id,parentid) values (13,11);
insert into country_relation (id,parentid) values (14,11);
insert into country_relation (id,parentid) values (15,11);
insert into country_relation (id,parentid) values (16,11);

     level
----------
         4

已用时间: 00: 00: 00.03

select name from
(
select b.name, connect_by_isleaf "isleaf"
from COUNTRY_RELATION a inner join country b on (a.id = b.id)
start with a.parentid is NULL connect by prior a.id = a.PARENTID
) T where T."isleaf" = 1;

NAME
--------------------------------------------------
Canada
Central America
Island Nations
Alabama
Alaska
Arizona
Arkansas
California
South America
Europe
Asia
Africa
Australia

已选择13行。

已用时间: 00: 00: 00.01

select connect_by_root b.name
from COUNTRY_RELATION a inner join country b on (a.id = b.id)
start with a.parentid is NULL connect by a.id = a.PARENTID

CONNECT_BY_ROOTB.NAME
--------------------------------------------------
Earth

已用时间: 00: 00: 00.01

select sys_connect_by_path(b.name,'/') "path"
from COUNTRY_RELATION a inner join country b on (a.id = b.id)
start with a.parentid is NULL connect by prior a.id = a.PARENTID
order by level,a.id;

path
--------------------------------------------------
/Earth
/Earth/North America
/Earth/South America
/Earth/Europe
/Earth/Asia
/Earth/Africa
/Earth/Australia
/Earth/North America/Canada
/Earth/North America/Central America
/Earth/North America/Island Nations
/Earth/North America/United States
/Earth/North America/United States/Alabama
/Earth/North America/United States/Alaska
/Earth/North America/United States/Arizona
/Earth/North America/United States/Arkansas
/Earth/North America/United States/California

已选择16行。

已用时间: 00: 00: 00.01

mysql> SELECT b.`name` AS root_node FROM
    -> (
    -> SELECT id FROM country_relation WHERE parentid IS NULL
    -> ) AS a, country AS b WHERE a.id = b.id;
+-----------+
| root_node |
+-----------+
| Earth |
+-----------+
1 row in set (0.00 sec)

mysql> SELECT b.`name` AS leaf_node FROM
    -> (
    -> SELECT id FROM country_relation WHERE id NOT IN (SELECT IFNULL(parentid,
-1) FROM country_relation)
    -> ) AS a, country AS b WHERE a.id = b.id;
+-----------------+
| leaf_node |
+-----------------+
| South America |
| Europe |
| Asia |
| Africa |
| Australia |
| Canada |
| Central America |
| Island Nations |
| Alabama |
| Alaska |
| Arizona |
| Arkansas |
| California |
+-----------------+
13 rows in set (0.00 sec)

mysql>

USE `t_girl`$$

DROP PROCEDURE IF EXISTS `sp_show_list`$$

CREATE DEFINER=`root`@`localhost` PROCEDURE `sp_show_list`()
BEGIN
      -- Created by ytt 2014/11/04.
      -- Is equal to oracle's connect by syntax.
      -- Body.
      DROP TABLE IF EXISTS tmp_country_list;
      CREATE TEMPORARY TABLE tmp_country_list (node_level INT UNSIGNED NOT NULL, node_path VARCHAR(1000) NOT NULL);
      -- Get the root node.
      INSERT INTO tmp_country_list SELECT 1, CONCAT('/',id) FROM country_relation WHERE parentid IS NULL;
      -- Loop within all parent node.
      cursor1:BEGIN
        DECLARE done1 INT DEFAULT 0;
        DECLARE i1 INT DEFAULT 1;
        DECLARE v_parentid INT DEFAULT -1;
        DECLARE v_node_path VARCHAR(1000) DEFAULT '';
        DECLARE cr1 CURSOR FOR SELECT parentid FROM country_relation WHERE parentid IS NOT NULL GROUP BY parentid ORDER BY parentid ASC;
        DECLARE CONTINUE HANDLER FOR NOT FOUND SET done1 = 1;
       
        OPEN cr1;
       
        loop1:LOOP
          FETCH cr1 INTO v_parentid;
          IF done1 = 1 THEN
            LEAVE loop1;
          END IF;
          SET i1 = i1 + 1;
         
          label_path:BEGIN
            DECLARE done2 INT DEFAULT 0;
            DECLARE CONTINUE HANDLER FOR NOT FOUND SET done2 = 1;
            -- Get the upper path.
            SELECT node_path FROM tmp_country_list WHERE node_level = i1 - 1 AND LOCATE(v_parentid,node_path) > 0 INTO v_node_path;
            -- Escape the outer not found exception.
            IF done2 = 1 THEN
              SET done2 = 0;
            END IF;
            INSERT INTO tmp_country_list
            SELECT i1,CONCAT(IFNULL(v_node_path,''),'/',id) FROM country_relation WHERE parentid = v_parentid;
          END;
        END LOOP;
       
        CLOSE cr1;
       
      END;
      -- Update node's id to its real name.
      update_name_label:BEGIN
        DECLARE cnt INT DEFAULT 0;
        DECLARE i2 INT DEFAULT 0;
        SELECT MAX(node_level) FROM tmp_country_list INTO cnt;
        WHILE i2 < cnt
        DO
          UPDATE tmp_country_list AS a, country AS b
          SET a.node_path = REPLACE(a.node_path,CONCAT('/',b.id),CONCAT('/',b.name))
          WHERE LOCATE(CONCAT('/',b.id),a.node_path) > 0;
          SET i2 = i2 + 1;
        END WHILE;
      END;
    
     SELECT node_path FROM tmp_country_list;
    END$$

DELIMITER ;

Query OK, 0 rows affected (0.08 sec)

mysql>