mysql无限级分类实现基于汇报关系的信息管理权限

汇报关系和家族族谱的实现类似，采用树的数据结构进行定义，树采用递归进行定义。即要嘛是一个根节点，要嘛是由一个根节点和其子树组成。OA中的汇报关系也采用这种结构（与树稍有不同），除董事长外，其他人有且只有一个非其本人的直接主管，董事长的直接主管和越级主管是其本人。从以上的定义其实可以看出，汇报关系类似树，但又与树并不完全相同。除董事长外，其他汇报关系均是树形结构。树形结构采用递归定义，如采用递归查询是非常耗时的操作。比如以下需求：
1.主管可以看到所有直线下属的绩效信息；
针对以上需求，我们提出三种方法
1.递归：如果采用树递归进行查询，对于庞大的数据量和较深的层级来说是比较耗时的。
2.父类id前缀：即父id为fid，子类编码规则则是以fid为前缀，查询的时候采用like，这种方法的缺点是1.不符合数据库规范要求；2.修改和移动耗时或不便
以下采用一种mysql无限级分类的方法来实现基于汇报关系的信息管理权限。
先了解一下mysql的无限级分类实现方法——改进前序遍历树
以下图为例，先把树按照水平方式摆开。从根节点开始（“Food”），然后他的左边写上1。然后按照树的顺序（从上到下）给“Fruit”的左边写上2。这样，你沿着树的边界（这就是“遍历”），然后同时在每个节点的左边和右边写上数字。最后，我们回到了根节点“Food”在右边写上18。下面是标上了数字的树，同时把遍历的顺序用箭头标出来了。


我们称这些数字为左值和右值（如，“Food”的左值是1，右值是18）。正如你所见，这些数字按时了每个节点之间的关系。因为“Red”有3和6两个值，所以，它是有拥有1-18值的“Food”节点的后续。同样的，我们可以推断所有左值大于2并且右值小于11的节点，都是有2-11的“Fruit” 节点的后续。这样，树的结构就通过左值和右值储存下来了。这种数遍整棵树算节点的方法叫做“改进前序遍历树”算法。
该算法具有据存储冗余小、直观性强；方便返回整个树型结构数据；可以很轻松的返回某一子树（方便分层加载）；快整获以某节点的祖谱路径；插入、删除、移动节点效率高等特点。
我们需要解决的最集中问题是查询效率。从图上看，我们如果查询Fruit的所有子类，只需要查询其左值>父结点左值&&右值小于父节点右值的节点。其查询时间复杂度是常数阶O(1)，而最有利的子树查询算法也是对数阶O（lgn）。从时间复杂度角度该算法的查询效率是达到最优的。
在本方法中主要采用两张表来实现，一张是汇报关系生成方法2格式的汇报关系对照表，第二张用于存储生成的改进前序遍历树
表1 tmpList定义如下：

SET FOREIGN_KEY_CHECKS=0;

-- ----------------------------
-- Table structure for tmplst
-- ----------------------------
DROP TABLE IF EXISTS `tmplst`;
CREATE TABLE `tmplst` (
`id` varchar(50) DEFAULT NULL,
`pid` varchar(50) DEFAULT NULL,
`leapfrogLeaderCode` varchar(50) DEFAULT NULL,
`nLevel` int(11) DEFAULT NULL,
`sCort` varchar(8000) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

表2 tree_node定义如下：

SET FOREIGN_KEY_CHECKS=0;

-- ----------------------------
-- Table structure for tree_node
-- ----------------------------
DROP TABLE IF EXISTS `tree_node`;
CREATE TABLE `tree_node` (
`id` varchar(20) NOT NULL DEFAULT '' COMMENT '工号',
`pid` varchar(20) DEFAULT NULL COMMENT '直接主管工号',
`leapfrogLeaderCode` varchar(20) DEFAULT NULL COMMENT '越级主管工号',
`leftId` int(50) DEFAULT NULL COMMENT '前序遍历树右节点左节点',
`rightId` int(50) DEFAULT NULL COMMENT '前序遍历树右节点',
`treeid` varchar(50) NOT NULL DEFAULT 'hbgx',
PRIMARY KEY (`id`),
KEY `idx_tree_node_leftId` (`leftId`) USING BTREE,
KEY `idx_tree_node_rightId` (`rightId`) USING BTREE
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

由于汇报关系并不是简单的树形结构，第一个节点即根节点是特殊的。所以这个节点作为特殊节点单独插入，采用如下存储过程：

ExitLabel:BEGIN
DECLARE vLeftId INT;
DECLARE aff INT;

SELECT `leftId` INTO vLeftId
FROM `tree_node`
WHERE `id`= rootid AND `pid` = 0;

IF vLeftId IS NOT NULL THEN

LEAVE ExitLabel;
END IF;

START TRANSACTION;

INSERT INTO `tree_node`(`id`,`pid`,`leftId`,`rightId`,`leapfrogLeaderCode`)
VALUES (rootid,0,1,2,rootid);

SELECT ROW_COUNT() INTO aff;

IF aff = 1 THEN
COMMIT;

ELSE
ROLLBACK;

END IF;
END

生成tmpList数据

BEGIN
DECLARE Level int ;
DECLARE pid VARCHAR(50);
DECLARE id VARCHAR(50);
DECLARE leapfrogLeaderCode VARCHAR(50);

drop TABLE IF EXISTS tmpLst;
CREATE TABLE tmpLst (
id varchar(50),
pid varchar(50),
leapfrogLeaderCode varchar(50),
nLevel int,
sCort varchar(8000)
);

Set Level=0 ;
INSERT into tmpLst SELECT staffId,directLeaderCode,leapfrogLeaderCode,Level,staffId FROM t_per_staffinfo WHERE  directLeaderCode=rootid;
WHILE ROW_COUNT()>0 DO
SET Level=Level+1 ;
INSERT into tmpLst
SELECT A.staffId,A.directLeaderCode,A.leapfrogLeaderCode,Level,concat(B.sCort,A.staffId) FROM t_per_staffinfo A,tmpLst B
WHERE  A.directLeaderCode=B.ID AND B.nLevel=Level-1  ;
END WHILE;

END

生成的数据格式如下：




id是员工工号，pid是直接主管工号，leapfrogLeaderCode是越级主管工号，nLevel是层数，sCort是方法2生成的父节点前缀工号
根据tmpList生成tree_node的存储过程 ：
插入操作很简单找到其父节点，之后把左值和右值大于父节点左值的节点的左右值加上2，之后再插入本节点，左右值分别为父节点左值加一和加二，可以用一个存储过程来操作：

ExitLabel:BEGIN
DECLARE vRightId INT;
DECLARE vTreeId varchar(50);
DECLARE aff INT;
DECLARE af INT DEFAULT 0;

SELECT `rightId` INTO vRightId
FROM `tree_node`
WHERE `id`= pid;

IF vRightId IS NULL THEN

LEAVE ExitLabel;
END IF;

START TRANSACTION;

UPDATE `tree_node`
SET `leftId`=`leftId`+2
WHERE `leftId` > vRightId;

SELECT ROW_COUNT() INTO aff;
SET af = aff+af;

UPDATE `tree_node`
SET `rightId`=`rightId`+2
WHERE  `rightId` >= vRightId;

SELECT ROW_COUNT() INTO aff;
SET af = aff+af;

INSERT INTO `tree_node`(`id`,`pid`,`leftId`,`rightId`,`leapfrogLeaderCode`)
VALUES (code,pid,vRightId,vRightId+1,leapfrogLeaderCode);

SELECT ROW_COUNT() INTO aff;
SET af = aff+af;

IF af >= 2 THEN
COMMIT;

ELSE
ROLLBACK;

END IF;
END

生成的改进前序遍历树数据如下：


前序遍历树数据生成以后，在需要使用以汇报关系做为基准的数据范围查询中增加如下代码：

<!-- 查询当前工号的汇报关系下属 -->
<select id="queryTreeNodeByStaffid" parameterType="String" resultMap="UserResultMap">
SELECT u.* FROM T_SYS_USER u LEFT JOIN tree_node t ON u.staffId = t.id
WHERE
u.userStatus = 'normal'
and
<![CDATA[ t.leftId > (SELECT leftId FROM tree_node treenode WHERE treenode.id = #{staffId}) ]]>
AND
<![CDATA[ t.rightId < (SELECT rightId FROM tree_node treenode WHERE treenode.id = #{staffId}) ]]>
</select>

由于汇报关系并不是一成不变的，在汇报关系出现变化时，应该修改tree_node表以适应最新的变化，使基于汇报关系的数据范围查询更加准确，以下存储过程是修改遍历表的：
1.

ExitLabel:BEGIN
call moveTreeNode(nodeId,pid,resultCode,resultMsg);

IF resultCode=1000 THEN

UPDATE `tree_node`
SET `leapfrogLeaderCode` = leapfrogLeaderCode
WHERE `id`= nodeId;

COMMIT;
END IF;
END

2.

ExitLabel:BEGIN

DECLARE vLeftId INT;
DECLARE vRightId INT;
DECLARE vTreeId varchar(50);
DECLARE vPid varchar(50);

DECLARE vTargetLeftId INT;
DECLARE vTargetRightId INT;
DECLARE vDiff INT;
DECLARE vLevelDiff INT;
DECLARE vGroupTreeId INT;
DECLARE vGroupIdStr varchar(1000);

SELECT `leftId`,`rightId`,`treeId`,`pid`
INTO vLeftId,vRightId,vTreeId,vPid
FROM `tree_node`
WHERE `id`= nodeId;

IF vLeftId IS NULL THEN
SET resultCode = 1002;
SET resultMsg = "要移动的节点不存在";
LEAVE ExitLabel;
END IF;

IF vLeftId=1 THEN
SET resultCode = 1003;
SET resultMsg = "根节点不能移动";
LEAVE ExitLabel;
END IF;

IF nodeId = targetId THEN
SET resultCode = 1004;
SET resultMsg = "不能移动到自己";
LEAVE ExitLabel;
END IF;

IF vPid = targetId THEN
SET resultCode = 1000;
SET resultMsg = "目标节点是要移动节点的父节点，不需要移动";
LEAVE ExitLabel;
END IF;

SELECT `leftId`,`rightId`
INTO vTargetLeftId,vTargetRightId
FROM `tree_node`
WHERE `treeId` = vTreeId AND `id`= targetId;

IF vTargetLeftId IS NULL THEN
SET resultCode = 1006;
SET resultMsg = "目标节点不存在";
LEAVE ExitLabel;
END IF;

IF vTargetLeftId > vLeftId AND vTargetLeftId < vRightId THEN
SET resultCode = 1007;
SET resultMsg = "目标节点不能是要移动节点的子节点";
LEAVE ExitLabel;
END IF;

START TRANSACTION;

SELECT `treeId`, group_concat(CAST(`id` as char)) as idStr
INTO vGroupTreeId,vGroupIdStr
FROM `tree_node`
WHERE `treeId` = vTreeId
AND `leftId` between vLeftId AND vRightId
GROUP BY `treeId`;

IF vTargetLeftId>vLeftId OR (vTargetLeftId < vLeftId AND vTargetRightId > vRightId) THEN

SET vDiff = vTargetRightId - 1 - vRightId;

UPDATE `tree_node`
SET `leftId`=`leftId` +vDiff,
`rightId`=`rightId` + vDiff

WHERE `treeId` = vTreeId
AND `leftId` between vLeftId AND vRightId;

UPDATE `tree_node`
SET `pid` = targetId
WHERE `id`= nodeId;

SET vDiff = vRightId-vLeftId+1;

UPDATE `tree_node`
SET `leftId`=`leftId`- vDiff
WHERE `treeId` = vTreeId
AND `leftId`>vRightId AND `leftId`< vTargetRightId
AND NOT FIND_IN_SET(CAST(`id` as char),vGroupIdStr);

UPDATE `tree_node`
SET `rightId`=`rightId`- vDiff
WHERE `treeId` = vTreeId
AND `rightId`>vRightId AND `rightId`< vTargetRightId
AND NOT FIND_IN_SET(CAST(`id` as char),vGroupIdStr);
ELSE

SET vDiff = vLeftId - vTargetRightId;

UPDATE `tree_node`
SET `leftId`=`leftId` -vDiff,
`rightId`=`rightId` - vDiff

WHERE `treeId` = vTreeId
AND `leftId` between vLeftId AND vRightId;

UPDATE `tree_node`
SET `pid` = targetId
WHERE `id`= nodeId;

SET vDiff = vRightId-vLeftId+1;

UPDATE `tree_node`
SET `leftId`=`leftId`+ vDiff
WHERE `treeId` = vTreeId
AND `leftId`>vTargetRightId AND `leftId`< vRightId
AND NOT FIND_IN_SET(CAST(`id` as char),vGroupIdStr);

UPDATE `tree_node`
SET `rightId`=`rightId`+ vDiff
WHERE `treeId` = vTreeId
AND `rightId`>=vTargetRightId AND `rightId`< vRightId
AND NOT FIND_IN_SET(CAST(`id` as char),vGroupIdStr);
END IF;

COMMIT;
SET resultCode = 1000;
SET resultMsg = "成功";
END

3.删除
删除的原理：
得到要删除节点的左右值，并得到他们的差再加一，@mywidth = @rgt - @lft + 1;

删除左右值在本节点之间的节点

修改条件为大于本节点右值的所有节点，操作为把他们的左右值都减去@mywidth

只允许删除叶子节点，如需删除叶子节点，先移动该节点不叶子节点，然后删除

ExitLabel:BEGIN
DECLARE vLeftId INT;
DECLARE vRightId INT;

DECLARE aff INT; /*影响记录条数*/
DECLARE af INT DEFAULT 0; /*影响记录总条数*/

SELECT `leftId`,`rightId`
INTO vLeftId,vRightId
FROM `tree_node`
WHERE `id` = nodeId;

IF vLeftId IS NULL THEN

LEAVE ExitLabel;
END IF;

IF vLeftId=1 THEN

LEAVE ExitLabel;
END IF;

START TRANSACTION;

DELETE
FROM `tree_node`
WHERE `leftId` between vLeftId AND vRightId;

SELECT ROW_COUNT() INTO aff;
SET af = aff+af;

UPDATE `tree_node`
SET `leftId`=`leftId`-(vRightId-vLeftId+1)
WHERE `treeId` = vTreeId AND `leftId`>vLeftId;

SELECT ROW_COUNT() INTO aff;
SET af = aff+af;

UPDATE `tree_node`
SET `rightId`=`rightId`-(vRightId-vLeftId+1)
WHERE  `rightId`>vLeftId;

SELECT ROW_COUNT() INTO aff;
SET af = aff+af;

IF af >= 2 THEN
COMMIT;

ELSE
ROLLBACK;

END IF;
END

调用如下存储过程实现更新和插入

BEGIN

DECLARE a VARCHAR(30);
DECLARE b VARCHAR(30);
DECLARE c VARCHAR(30);

DECLARE str VARCHAR(300);
DECLARE x int;

DECLARE s int default 0;

DECLARE cursor_name CURSOR FOR select pid,id,leapfrogLeaderCode from tmpLst;

DECLARE CONTINUE HANDLER FOR SQLSTATE '02000' SET s=1;

set str = "--";

OPEN cursor_name;

fetch  cursor_name into a,b,c;

while s <> 1 do
set str =  concat(str,x);

call addTreeNode(a ,b,c);

fetch  cursor_name into a,b,c;

end while;

CLOSE cursor_name ;

select str;

END

总的调用次序

call showTreeNodes_yongyupost2000('FXGG0001');
TRUNCATE tree_node ;
call addTreeRootNode('FXGG0001');
call add_test()

由于移动的代码比较晦涩难懂，我们采用的是tree_node定时trancate，重新生成的方式，周期为一天一次。
参考资料：

应用mysql数据库设计无限级分类表

mysql存储过程实现的无限级分类，前序遍历树（本文的代码主要参考该文章）
SQL Server存储层级数据实现无限级分类
一个带存储过程的无限级分类数据库设计

[原创]另类非递归的无限级分类(存储过程版)