MySQL-邻接列表模型-获取深度
我有一个组织表,它有一个MySQL-邻接列表模型-获取深度,mysql,adjacency-list,Mysql,Adjacency List,我有一个组织表,它有一个id、一个parent\u id和一个name列。此表中大约有5万行。只有一个顶级家长,其余的都在这个级别之下。在Oracle中,我可以通过级别伪列轻松检索特定组织的当前深度: SELECT id, parent_id, level, name FROM organizations START WITH parent_id = 1 CONNECT BY PRIOR id = parent_id 我不知道在MySQL中执行上述操作的正确方法是什么。我需要在一个查询中获取整
id
、一个parent\u id
和一个name
列。此表中大约有5万行。只有一个顶级家长,其余的都在这个级别之下。在Oracle中,我可以通过级别
伪列轻松检索特定组织的当前深度:
SELECT id, parent_id, level, name
FROM organizations
START WITH parent_id = 1
CONNECT BY PRIOR id = parent_id
我不知道在MySQL中执行上述操作的正确方法是什么。我需要在一个查询中获取整个树以及节点的深度
关于StackOverflow,有很多问题都与此有关,但似乎没有一个真正好的答案,大部分都是指向解决方案可疑的博客的链接。以某种直截了当的方式,这肯定是可行的
不幸的是,以任何方式修改表都不是一个选项,因此嵌套集是不可能的。没有CTEs/子查询分解,SQL中就没有递归,因此在“纯SQL”中,特别是在MySQL中实现的情况下,特别是在任意级别深度的情况下,绝对没有办法做到这一点。看 这就是为什么您找到的所有答案都是黑客,以绕过引擎的这一特定限制。如果您仍然需要此解决方案,可以尝试此解决方案:。(当然,这种限制意味着从LangSec的角度来看,解析查询并不奇怪,它允许进行各种有益的解析,并消除了一些安全问题,但对您没有任何帮助。)
大量的
左撇子加入了
s,它们耗尽了层次结构,很抱歉,这是一个糟糕的双关语。Mysql不支持递归sql。当你只有一个维度时,你可以在父维度上使用一个左连接。这真是太好笑了。昨天,我在一个类似的问题上得到了+50的悬赏:
我引用了(2011年10月24日)
我将发布相同的存储过程以及DBA StackExchange答案中的示例:
获取任何给定节点的父节点的代码
DELIMITER $$
DROP FUNCTION IF EXISTS `junk`.`GetParentIDByID` $$
CREATE FUNCTION `junk`.`GetParentIDByID` (GivenID INT) RETURNS INT
DETERMINISTIC
BEGIN
DECLARE rv INT;
SELECT IFNULL(parent_id,-1) INTO rv FROM
(SELECT parent_id FROM pctable WHERE id = GivenID) A;
RETURN rv;
END $$
DELIMITER ;
DELIMITER $$
DROP FUNCTION IF EXISTS `junk`.`GetAncestry` $$
CREATE FUNCTION `junk`.`GetAncestry` (GivenID INT) RETURNS VARCHAR(1024)
DETERMINISTIC
BEGIN
DECLARE rv VARCHAR(1024);
DECLARE cm CHAR(1);
DECLARE ch INT;
SET rv = '';
SET cm = '';
SET ch = GivenID;
WHILE ch > 0 DO
SELECT IFNULL(parent_id,-1) INTO ch FROM
(SELECT parent_id FROM pctable WHERE id = ch) A;
IF ch > 0 THEN
SET rv = CONCAT(rv,cm,ch);
SET cm = ',';
END IF;
END WHILE;
RETURN rv;
END $$
DELIMITER ;
DELIMITER $$
DROP FUNCTION IF EXISTS `junk`.`GetFamilyTree` $$
CREATE FUNCTION `junk`.`GetFamilyTree` (GivenID INT) RETURNS varchar(1024) CHARSET latin1
DETERMINISTIC
BEGIN
DECLARE rv,q,queue,queue_children VARCHAR(1024);
DECLARE queue_length,front_id,pos INT;
SET rv = '';
SET queue = GivenID;
SET queue_length = 1;
WHILE queue_length > 0 DO
SET front_id = FORMAT(queue,0);
IF queue_length = 1 THEN
SET queue = '';
ELSE
SET pos = LOCATE(',',queue) + 1;
SET q = SUBSTR(queue,pos);
SET queue = q;
END IF;
SET queue_length = queue_length - 1;
SELECT IFNULL(qc,'') INTO queue_children
FROM (SELECT GROUP_CONCAT(id) qc
FROM pctable WHERE parent_id = front_id) A;
IF LENGTH(queue_children) = 0 THEN
IF LENGTH(queue) = 0 THEN
SET queue_length = 0;
END IF;
ELSE
IF LENGTH(rv) = 0 THEN
SET rv = queue_children;
ELSE
SET rv = CONCAT(rv,',',queue_children);
END IF;
IF LENGTH(queue) = 0 THEN
SET queue = queue_children;
ELSE
SET queue = CONCAT(queue,',',queue_children);
END IF;
SET queue_length = LENGTH(queue) - LENGTH(REPLACE(queue,',','')) + 1;
END IF;
END WHILE;
RETURN rv;
END $$
获取任何给定节点的Ancenstry的代码
DELIMITER $$
DROP FUNCTION IF EXISTS `junk`.`GetParentIDByID` $$
CREATE FUNCTION `junk`.`GetParentIDByID` (GivenID INT) RETURNS INT
DETERMINISTIC
BEGIN
DECLARE rv INT;
SELECT IFNULL(parent_id,-1) INTO rv FROM
(SELECT parent_id FROM pctable WHERE id = GivenID) A;
RETURN rv;
END $$
DELIMITER ;
DELIMITER $$
DROP FUNCTION IF EXISTS `junk`.`GetAncestry` $$
CREATE FUNCTION `junk`.`GetAncestry` (GivenID INT) RETURNS VARCHAR(1024)
DETERMINISTIC
BEGIN
DECLARE rv VARCHAR(1024);
DECLARE cm CHAR(1);
DECLARE ch INT;
SET rv = '';
SET cm = '';
SET ch = GivenID;
WHILE ch > 0 DO
SELECT IFNULL(parent_id,-1) INTO ch FROM
(SELECT parent_id FROM pctable WHERE id = ch) A;
IF ch > 0 THEN
SET rv = CONCAT(rv,cm,ch);
SET cm = ',';
END IF;
END WHILE;
RETURN rv;
END $$
DELIMITER ;
DELIMITER $$
DROP FUNCTION IF EXISTS `junk`.`GetFamilyTree` $$
CREATE FUNCTION `junk`.`GetFamilyTree` (GivenID INT) RETURNS varchar(1024) CHARSET latin1
DETERMINISTIC
BEGIN
DECLARE rv,q,queue,queue_children VARCHAR(1024);
DECLARE queue_length,front_id,pos INT;
SET rv = '';
SET queue = GivenID;
SET queue_length = 1;
WHILE queue_length > 0 DO
SET front_id = FORMAT(queue,0);
IF queue_length = 1 THEN
SET queue = '';
ELSE
SET pos = LOCATE(',',queue) + 1;
SET q = SUBSTR(queue,pos);
SET queue = q;
END IF;
SET queue_length = queue_length - 1;
SELECT IFNULL(qc,'') INTO queue_children
FROM (SELECT GROUP_CONCAT(id) qc
FROM pctable WHERE parent_id = front_id) A;
IF LENGTH(queue_children) = 0 THEN
IF LENGTH(queue) = 0 THEN
SET queue_length = 0;
END IF;
ELSE
IF LENGTH(rv) = 0 THEN
SET rv = queue_children;
ELSE
SET rv = CONCAT(rv,',',queue_children);
END IF;
IF LENGTH(queue) = 0 THEN
SET queue = queue_children;
ELSE
SET queue = CONCAT(queue,',',queue_children);
END IF;
SET queue_length = LENGTH(queue) - LENGTH(REPLACE(queue,',','')) + 1;
END IF;
END WHILE;
RETURN rv;
END $$
获取任何给定节点的族树(或子体)的代码
DELIMITER $$
DROP FUNCTION IF EXISTS `junk`.`GetParentIDByID` $$
CREATE FUNCTION `junk`.`GetParentIDByID` (GivenID INT) RETURNS INT
DETERMINISTIC
BEGIN
DECLARE rv INT;
SELECT IFNULL(parent_id,-1) INTO rv FROM
(SELECT parent_id FROM pctable WHERE id = GivenID) A;
RETURN rv;
END $$
DELIMITER ;
DELIMITER $$
DROP FUNCTION IF EXISTS `junk`.`GetAncestry` $$
CREATE FUNCTION `junk`.`GetAncestry` (GivenID INT) RETURNS VARCHAR(1024)
DETERMINISTIC
BEGIN
DECLARE rv VARCHAR(1024);
DECLARE cm CHAR(1);
DECLARE ch INT;
SET rv = '';
SET cm = '';
SET ch = GivenID;
WHILE ch > 0 DO
SELECT IFNULL(parent_id,-1) INTO ch FROM
(SELECT parent_id FROM pctable WHERE id = ch) A;
IF ch > 0 THEN
SET rv = CONCAT(rv,cm,ch);
SET cm = ',';
END IF;
END WHILE;
RETURN rv;
END $$
DELIMITER ;
DELIMITER $$
DROP FUNCTION IF EXISTS `junk`.`GetFamilyTree` $$
CREATE FUNCTION `junk`.`GetFamilyTree` (GivenID INT) RETURNS varchar(1024) CHARSET latin1
DETERMINISTIC
BEGIN
DECLARE rv,q,queue,queue_children VARCHAR(1024);
DECLARE queue_length,front_id,pos INT;
SET rv = '';
SET queue = GivenID;
SET queue_length = 1;
WHILE queue_length > 0 DO
SET front_id = FORMAT(queue,0);
IF queue_length = 1 THEN
SET queue = '';
ELSE
SET pos = LOCATE(',',queue) + 1;
SET q = SUBSTR(queue,pos);
SET queue = q;
END IF;
SET queue_length = queue_length - 1;
SELECT IFNULL(qc,'') INTO queue_children
FROM (SELECT GROUP_CONCAT(id) qc
FROM pctable WHERE parent_id = front_id) A;
IF LENGTH(queue_children) = 0 THEN
IF LENGTH(queue) = 0 THEN
SET queue_length = 0;
END IF;
ELSE
IF LENGTH(rv) = 0 THEN
SET rv = queue_children;
ELSE
SET rv = CONCAT(rv,',',queue_children);
END IF;
IF LENGTH(queue) = 0 THEN
SET queue = queue_children;
ELSE
SET queue = CONCAT(queue,',',queue_children);
END IF;
SET queue_length = LENGTH(queue) - LENGTH(REPLACE(queue,',','')) + 1;
END IF;
END WHILE;
RETURN rv;
END $$
为了演示所有操作的执行,下面是示例数据
USE junk
DROP TABLE IF EXISTS pctable;
CREATE TABLE pctable
(
id INT NOT NULL AUTO_INCREMENT,
parent_id INT,
PRIMARY KEY (id)
) ENGINE=MyISAM;
INSERT INTO pctable (parent_id) VALUES (0);
INSERT INTO pctable (parent_id) SELECT parent_id+1 FROM pctable;
INSERT INTO pctable (parent_id) SELECT parent_id+2 FROM pctable;
INSERT INTO pctable (parent_id) SELECT parent_id+3 FROM pctable;
INSERT INTO pctable (parent_id) SELECT parent_id+4 FROM pctable;
INSERT INTO pctable (parent_id) SELECT parent_id+5 FROM pctable;
SELECT * FROM pctable;
下面是查看所有父母、祖先和族谱的查询
SELECT
id,parent_id,
GetParentIDByID(id),
GetAncestry(id),
GetFamilyTree(id)
FROM pctable;
试试看 @idok,如果您有多个子项的相同父id,则函数将返回“截断的不正确的双精度值”错误。我从dba找到了以下修复方法,它是由Sivakumar Natarayan提供的
WHILE queue_length > 0 DO
IF queue_length = 1 THEN
SET front_id = queue;
SET queue = '';
ELSE
SET front_id = SUBSTR(queue,1,LOCATE(',',queue)-1);
SET pos = LOCATE(',',queue) + 1;
SET q = SUBSTR(queue,pos);
SET queue = q;
END IF;
我得到一个错误1292(22007):getFamilyTree截断了不正确的双精度值:“4,5”。有没有关于为什么会发生这种情况的建议!?感谢您的GetGenestory函数基本上是使用LazyLoad时JSTree搜索函数的完美解决方案。谢谢你,伙计!2019年,MySQL和MariaDB支持CTE的可能重复