juda dos dados hierárquicos do @MySQL - Método da tabela de fechamento

Estou tentando implementar um sistema no MySQL para armazenar dados hierárquicos. Eu decidi ir com o sistema implementadoaqu como descrito porBill Karwin começando no slide número 40. Estou tentando configurar o banco de dados para que oEntryPaths tabela é mantida automaticament

Atualizar Eu atualizei o banco de dados crie um pouco de SQL. Eu tenho as coisas 1/2 trabalhando para uma atualização, eu acho. Depois de executar o banco de dados, crie SQL, tente o seguinte

Primeiro, veja como esta entrada se parece

-- 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`

E como este parece

-- 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`

A primeira entrada visualizada tem vários filhos, a segunda não tem filhos. Execute a seguinte atualização para reparar o nó 'Anos da faculdade' (e seus filhos) paraJohn Doe

UPDATE  `Library` SET  `subsectionOf` =  0x08 WHERE  `Library`.`iD` = 0x04;

Se você executar novamente as duas instruções de seleção acima, verá que os itens foram removidos deJane Doe mas eles não foram adicionados aJohn Doe como esperado. OLibrary_Update O gatilho está com defeito, mas estou sem ideias para tentar consertá-l

O banco de dados cria SQL com dados de exemplo:

-- 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');

questionAnswers(1)

yourAnswerToTheQuestion