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MySQLに階層データを格納するシステムを実装しようとしています。スライド番号40から始まるBillKarwinによって説明されているように、ここに実装されているシステムを使用することにしました。テーブルが自動的に維持されるようにデータベースをセットアップしようとしています。EntryPaths

更新：データベースを更新してSQLを作成しました。更新のために1/2が機能していると思います。データベースを実行した後、SQLを作成して次のことを試してください

まず、このエントリがどのように見えるかを確認します

-- 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`

そしてこれはどのように見えるか

-- 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`

表示された最初のエントリには複数の子があり、2番目のエントリには子がありません。次の更新を実行して、「CollegeYears」ノード（およびその子）の親を変更します。John Doe

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

上記の2つのselectステートメントを再実行すると、アイテムが削除されJane Doeたが、期待どおりに追加されていないことがわかりますJohn Doe。トリガーに問題がありますLibrary_Updateが、修正しようとするアイデアが不足しています。

データベースは、サンプルデータを使用してSQLを作成します。

-- 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');
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1 に答える 1

1

Libary_UpdateトリガーのINSERTステートメントには、次の行があります。

WHERE subtree.`ancestor` = NEW.`iD`

ただし、IDフィールドを更新していないため、NEW.iD値はないと思います。その行はおそらく代わりにOLD.iDを使用する必要がありますか？

于 2011-11-23T15:28:49.403 に答える