Я пытаюсь реализовать систему в MySQL для хранения иерархических данных.Я решил пойти с системой, реализованной здесь , как описано Биллом Карвином , начиная со слайда № 40. Я пытаюсь настроить базу данных, чтобы поддерживать таблицу EntryPathsавтоматически.
Обновление: Я немного обновил базу данных для создания SQL.Я думаю, у меня есть вещи, работающие на обновление.После запуска базы данных создайте SQL, попробуйте следующее
Сначала посмотрите, как выглядит эта запись
-- Example query to return a full library entry (0x02 is the entry iD)
SELECT `Library`.* FROM `Library`
LEFT JOIN `EntryPaths` ON `Library`.`iD` = `EntryPaths`.`descendant`
WHERE `EntryPaths`.`ancestor` = 0x02
ORDER BY `Library`.`subsectionOf`, `Library`.`subsectionOrder`
И как эта запись выглядит
-- Example query to return a full library entry (0x08 is the entry iD)
SELECT `Library`.* FROM `Library`
LEFT JOIN `EntryPaths` ON `Library`.`iD` = `EntryPaths`.`descendant`
WHERE `EntryPaths`.`ancestor` = 0x08
ORDER BY `Library`.`subsectionOf`, `Library`.`subsectionOrder`
Первая просмотренная запись имеет несколькодети, у второго детей нет.Запустите следующее обновление, чтобы переписать узел «Годы колледжа» (и его дочерние элементы) на John Doe
UPDATE `Library` SET `subsectionOf` = 0x08 WHERE `Library`.`iD` = 0x04;
Если вы повторно запустите два вышеупомянутых оператора выбора, вы увидите, что элементы были удалены изJane Doe но они не были добавлены к John Doe, как ожидалось.Триггер Library_Update неисправен, но у меня заканчиваются идеи, чтобы попытаться это исправить.
База данных создает SQL с примерами данных:
-- MYSQL
SET FOREIGN_KEY_CHECKS=0;
DROP TRIGGER IF EXISTS Library_Insert;
DROP TRIGGER IF EXISTS Library_Update;
DROP TABLE IF EXISTS Users;
DROP TABLE IF EXISTS Attributes;
DROP TABLE IF EXISTS LibraryHistory;
DROP TABLE IF EXISTS EntryPaths;
DROP TABLE IF EXISTS Library;
SET FOREIGN_KEY_CHECKS=1;
CREATE TABLE `Users` (
`iD` VARBINARY(16) NOT NULL, -- UUID & PK
`libraryID` VARBINARY(16), -- Library UUID & FK (The library entry for this person)
`email` NVARCHAR(255) NOT NULL, -- Email address
`nickname` NVARCHAR(255) NOT NULL, -- Nickname used for display
`firstname` NVARCHAR(255), -- Real first name
`lastname` NVARCHAR(255), -- Real last name
`joinDate` DATETIME NOT NULL, -- Date the account was created
PRIMARY KEY (`iD`)
) ENGINE = MYISAM;
CREATE TABLE `Library` (
`iD` VARBINARY(16) NOT NULL, -- UUID & PK
`name` NVARCHAR(500) NOT NULL, -- Name for the entry
`contentType` NVARCHAR(50) NOT NULL, -- Mime type of data
`content` LONGBLOB NOT NULL, -- Data a for the entry
`subsectionOf` VARBINARY(16), -- Library UUID & FK
`subsectionOrder` INT, -- Oder of Subsections
`lastModifiedBy` VARBINARY(16), -- User UUID & FK
`lastModified` DATETIME NOT NULL, -- Last time the record was updated
PRIMARY KEY (`iD`),
FOREIGN KEY (`subsectionOf`) REFERENCES Library(`iD`) ON DELETE CASCADE,
FOREIGN KEY (`lastModifiedBy`) REFERENCES Users(`iD`),
INDEX(`name`)
) ENGINE = MYISAM;
-- Trigger to update the EntryPaths table for new entries
DELIMITER //
CREATE TRIGGER `Library_Insert` AFTER INSERT ON `Library` FOR EACH ROW
BEGIN
INSERT INTO `EntryPaths` (`ancestor`, `descendant`, `len`)
SELECT `ancestor`, NEW.`iD`, len + 1 FROM `EntryPaths`
WHERE `descendant` = NEW.`subsectionOf`
UNION ALL SELECT NEW.`iD`, NEW.`iD`, 0;
END; //
DELIMITER ;
DELIMITER //
CREATE TRIGGER `Library_Update` BEFORE UPDATE ON `Library` FOR EACH ROW
BEGIN
-- Add the old entry into the history table
INSERT INTO `LibraryHistory` VALUES(UNHEX(REPLACE(UUID(),'-','')),
OLD.`iD`, OLD.`name`, OLD.`contentType`, OLD.`content`,
OLD.`subsectionOf`, OLD.`subsectionOrder`, OLD.`lastModifiedBy`,
OLD.`lastModified`);
-- From http://www.mysqlperformanceblog.com/2011/02/14/moving-subtrees-in-closure-table/
IF OLD.`subsectionOf` != NEW.`subsectionOf` THEN
-- Remove the node from its current parent
DELETE a FROM `EntryPaths` AS a
JOIN `EntryPaths` AS d ON a.`descendant` = d.`descendant`
LEFT JOIN `EntryPaths` AS x
ON x.`ancestor` = d.`ancestor` AND x.`descendant` = a.`ancestor`
WHERE d.`ancestor` = OLD.`iD` AND x.`ancestor` IS NULL;
-- Add the node to its new parent
-- FIXME: Not Working yet
INSERT `EntryPaths` (`ancestor`, `descendant`, `len`)
SELECT supertree.`ancestor`, subtree.`descendant`, supertree.`len`+subtree.`len`+1
FROM `EntryPaths` AS supertree JOIN `EntryPaths` AS subtree
WHERE subtree.`ancestor` = NEW.`iD`
AND supertree.`descendant` = NEW.`subsectionOf`;
END IF;
END; //
DELIMITER ;
CREATE TABLE `EntryPaths` (
`ancestor` VARBINARY(16) NOT NULL,
`descendant` VARBINARY(16) NOT NULL,
`len` VARBINARY(16) NOT NULL,
PRIMARY KEY (`ancestor`, `descendant`),
FOREIGN KEY (`ancestor`) REFERENCES Library(`iD`) ON DELETE CASCADE,
FOREIGN KEY (`descendant`) REFERENCES Library(`iD`) ON DELETE CASCADE
) ENGINE = MYISAM;
CREATE TABLE `LibraryHistory` (
`iD` VARBINARY(16) NOT NULL, -- UUID & PK
`libraryID` VARBINARY(16) NOT NULL, -- Library UUID & FK
`name` NVARCHAR(500) NOT NULL, -- Name for the entry
`contentType` NVARCHAR(50) NOT NULL, -- Mime type of data
`content` LONGBLOB NOT NULL, -- Data a for the entry
`subsectionOf` VARBINARY(16), -- Library UUID & FK
`subsectionOrder` INT, -- Oder of Subsections
`lastModifiedBy` VARBINARY(16), -- User UUID & FK
`lastModified` DATETIME NOT NULL, -- Last time the record was updated
PRIMARY KEY (`iD`),
FOREIGN KEY (`libraryID`) REFERENCES Library(`iD`) ON DELETE CASCADE,
FOREIGN KEY (`lastModifiedBy`) REFERENCES Users(`iD`)
) ENGINE = MYISAM;
CREATE TABLE `Attributes` (
`iD` VARBINARY(16) NOT NULL, -- UUID & PK (Potentially could be removed)
`libraryID` VARBINARY(16) NOT NULL, -- Library UUID & FK
`name` NVARCHAR(500) NOT NULL, -- Name of attribute
`dataType` INT NOT NULL, -- The type of data the attribute holds (int, date, string, etc.)
`data` NVARCHAR(500) NOT NULL, -- Value of attribute
`lastModifiedBy` VARBINARY(16), -- User UUID & FK
`lastModified` DATETIME NOT NULL, -- Last time the record was updated
PRIMARY KEY (`iD`),
FOREIGN KEY (`libraryID`) REFERENCES Library(`iD`) ON DELETE CASCADE,
INDEX (`name`)
) ENGINE = MYISAM;
ALTER TABLE `Users` ADD CONSTRAINT FK_User_Library FOREIGN KEY (`libraryID`) REFERENCES Library(`iD`);
-- Example Data
INSERT INTO `Library` VALUES(0x01, 'People', 'text/plain', 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam pulvinar scelerisque quam, vel convallis turpis porttitor in. Curabitur pulvinar fermentum pulvinar. Mauris lorem lacus, gravida porta lacinia vitae, dictum ac eros. Aliquam magna arcu, lacinia ac dictum sed, euismod eu elit. Sed semper nulla at velit pulvinar in vehicula risus tempus. Phasellus id nisl libero, id porttitor purus. Integer aliquet semper aliquam. Morbi elit mi, pellentesque et ornare nec, iaculis gravida elit. Sed in luctus lorem. Maecenas a purus at lectus condimentum congue.', NULL, NULL, NULL, '2011-11-16 20:27:54');
INSERT INTO `Library` VALUES(0x02, 'Jane Doe', 'text/x-markup', 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam pulvinar scelerisque quam, vel convallis turpis porttitor in. Curabitur pulvinar fermentum pulvinar. Mauris lorem lacus, gravida porta lacinia vitae, dictum ac eros. Aliquam magna arcu, lacinia ac dictum sed, euismod eu elit. Sed semper nulla at velit pulvinar in vehicula risus tempus. Phasellus id nisl libero, id porttitor purus. Integer aliquet semper aliquam. Morbi elit mi, pellentesque et ornare nec, iaculis gravida elit. Sed in luctus lorem. Maecenas a purus at lectus condimentum congue.', NULL, NULL, NULL, '2011-11-16 20:29:13');
INSERT INTO `Library` VALUES(0x03, 'Younger Years', 'text/x-markup', 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam pulvinar scelerisque quam, vel convallis turpis porttitor in. Curabitur pulvinar fermentum pulvinar. Mauris lorem lacus, gravida porta lacinia vitae, dictum ac eros. Aliquam magna arcu, lacinia ac dictum sed, euismod eu elit. Sed semper nulla at velit pulvinar in vehicula risus tempus. Phasellus id nisl libero, id porttitor purus. Integer aliquet semper aliquam. Morbi elit mi, pellentesque et ornare nec, iaculis gravida elit. Sed in luctus lorem. Maecenas a purus at lectus condimentum congue.', 0x02, 1, NULL, '2011-11-16 00:00:00');
INSERT INTO `Library` VALUES(0x04, 'College Years', 'text/x-markup', 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam pulvinar scelerisque quam, vel convallis turpis porttitor in. Curabitur pulvinar fermentum pulvinar. Mauris lorem lacus, gravida porta lacinia vitae, dictum ac eros. Aliquam magna arcu, lacinia ac dictum sed, euismod eu elit. Sed semper nulla at velit pulvinar in vehicula risus tempus. Phasellus id nisl libero, id porttitor purus. Integer aliquet semper aliquam. Morbi elit mi, pellentesque et ornare nec, iaculis gravida elit. Sed in luctus lorem. Maecenas a purus at lectus condimentum congue.', 0x02, 2, NULL, '2011-11-16 20:31:52');
INSERT INTO `Library` VALUES(0x05, 'Yale', 'text/x-markup', 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam pulvinar scelerisque quam, vel convallis turpis porttitor in. Curabitur pulvinar fermentum pulvinar. Mauris lorem lacus, gravida porta lacinia vitae, dictum ac eros. Aliquam magna arcu, lacinia ac dictum sed, euismod eu elit. Sed semper nulla at velit pulvinar in vehicula risus tempus. Phasellus id nisl libero, id porttitor purus. Integer aliquet semper aliquam. Morbi elit mi, pellentesque et ornare nec, iaculis gravida elit. Sed in luctus lorem. Maecenas a purus at lectus condimentum congue.', 0x04, 2, NULL, '2011-11-16 20:32:44');
INSERT INTO `Library` VALUES(0x06, 'Old Age', 'text/x-markup', 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam pulvinar find me here scelerisque quam, vel convallis turpis porttitor in. Curabitur pulvinar fermentum pulvinar. Mauris lorem lacus, gravida porta lacinia vitae, dictum ac eros. Aliquam magna arcu, lacinia ac dictum sed, euismod eu elit. Sed semper nulla at velit pulvinar in vehicula risus tempus. Phasellus id nisl libero, id porttitor purus. Integer aliquet semper aliquam. Morbi elit mi, pellentesque et ornare nec, iaculis gravida elit. Sed in luctus lorem. Maecenas a purus at lectus condimentum congue.', 0x02, 3, NULL, '2011-11-16 20:31:52');
INSERT INTO `Library` VALUES(0x07, 'Community College', 'text/x-markup', 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam pulvinar scelerisque quam, vel convallis turpis porttitor in. Curabitur pulvinar fermentum pulvinar. Mauris lorem lacus, gravida porta lacinia vitae, dictum ac eros. Aliquam magna arcu, lacinia ac dictum sed, euismod eu elit. Sed semper nulla at velit pulvinar in vehicula risus tempus. Phasellus id nisl libero, id porttitor purus. Integer aliquet semper aliquam. Morbi elit mi, pellentesque et ornare nec, iaculis gravida elit. Sed in luctus lorem. Maecenas a purus at lectus condimentum congue.', 0x04, 1, NULL, '2011-11-16 20:33:11');
INSERT INTO `Library` VALUES(0x08, 'John Doe', 'text/x-markup', 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam pulvinar scelerisque quam, vel convallis turpis porttitor in. Curabitur pulvinar fermentum pulvinar. Mauris lorem lacus, gravida porta lacinia vitae, dictum ac eros. Aliquam magna arcu, lacinia ac dictum sed, euismod eu elit. Sed semper nulla at velit pulvinar in vehicula risus tempus. Phasellus id nisl libero, id porttitor purus. Integer aliquet semper aliquam. Morbi elit mi, pellentesque et ornare nec, iaculis gravida elit. Sed in luctus lorem. Maecenas a purus at lectus condimentum congue.', NULL, NULL, NULL, '2011-11-16 20:34:40');
INSERT INTO `Library` VALUES(0x09, 'Planets', 'text/x-markup', 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam pulvinar scelerisque quam, vel convallis turpis porttitor in. Curabitur pulvinar fermentum pulvinar. Mauris lorem lacus, gravida porta lacinia vitae, dictum ac eros. Aliquam magna arcu, lacinia ac dictum sed, euismod eu elit. Sed semper nulla at velit pulvinar in vehicula risus tempus. Phasellus id nisl libero, id porttitor purus. Integer aliquet semper aliquam. Morbi elit mi, pellentesque et ornare nec, iaculis gravida elit. Sed in luctus lorem. Maecenas a purus at lectus condimentum congue.', NULL, NULL, NULL, '2011-11-16 20:27:54');
INSERT INTO `Library` VALUES(0x10, 'Earth', 'text/x-markup', 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam pulvinar scelerisque quam, vel convallis turpis porttitor in. Curabitur pulvinar fermentum pulvinar. Mauris lorem lacus, gravida porta lacinia vitae, dictum ac eros. Aliquam magna arcu, lacinia ac dictum sed, euismod eu elit. Sed semper nulla at velit pulvinar in vehicula risus tempus. Phasellus id nisl libero, id porttitor purus. Integer aliquet semper aliquam. Morbi elit mi, pellentesque et ornare nec, iaculis gravida elit. Sed in luctus lorem. Maecenas a purus at lectus condimentum congue.', NULL, NULL, NULL, '2011-11-16 20:27:54');
INSERT INTO `Library` VALUES(0x11, 'Mars', 'text/x-markup', 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam pulvinar scelerisque quam, vel convallis turpis porttitor in. Curabitur pulvinar fermentum pulvinar. Mauris lorem lacus, gravida porta lacinia vitae, dictum ac eros. Aliquam magna arcu, lacinia ac dictum sed, euismod eu elit. Sed semper nulla at velit pulvinar in vehicula risus tempus. Phasellus id nisl libero, id porttitor purus. Integer aliquet semper aliquam. Morbi elit mi, pellentesque et ornare nec, iaculis gravida elit. Sed in luctus lorem. Maecenas a purus at lectus condimentum congue.', NULL, NULL, NULL, '2011-11-16 20:27:54');
INSERT INTO `Attributes` VALUES(0x01, 0x02, 'TypeOf', 1, 0x01, NULL, '2011-11-16 20:34:40');
INSERT INTO `Attributes` VALUES(0x02, 0x02, 'BirthDate', 2, '19770521', NULL, '2011-11-16 20:34:40');
INSERT INTO `Attributes` VALUES(0x03, 0x02, 'EyeColor', 3, 'Brown', NULL, '2011-11-16 20:34:40');
INSERT INTO `Attributes` VALUES(0x04, 0x08, 'TypeOf', 1, 0x01, NULL, '2011-11-16 20:34:40');
INSERT INTO `Attributes` VALUES(0x05, 0x08, 'BirthDate', 2, '19740521', NULL, '2011-11-16 20:34:40');
INSERT INTO `Attributes` VALUES(0x06, 0x10, 'TypeOf', 1, 0x08, NULL, '2011-11-16 20:34:40');
INSERT INTO `Attributes` VALUES(0x07, 0x11, 'TypeOf', 1, 0x08, NULL, '2011-11-16 20:34:40');