SQL/MySQL/Join/Join Update
CROSS JOIN in update command
<source lang="sql">
/* mysql> select * from Authors; +--------+-----------------+------------------+----------------+ | AuthID | AuthorFirstName | AuthorMiddleName | AuthorLastName | +--------+-----------------+------------------+----------------+ | 1006 | Henry | S. | Thompson | | 1007 | Jason | Carol | Oak | | 1008 | James | NULL | Elk | | 1009 | Tom | M | Ride | | 1010 | Jack | K | Ken | | 1011 | Mary | G. | Lee | | 1012 | Annie | NULL | Wats | | 1013 | Alan | NULL | Wang | | 1014 | Nelson | NULL | Yin | +--------+-----------------+------------------+----------------+ 9 rows in set (0.01 sec) mysql> UPDATE Authors CROSS JOIN AuthorArticle USING (AuthID)
-> CROSS JOIN Articles USING (ArticleID) -> SET AuthorLastName="Watts" -> WHERE ArticleTitle="Information";
Query OK, 1 row affected (0.03 sec) Rows matched: 1 Changed: 1 Warnings: 0 mysql> select * from Authors; +--------+-----------------+------------------+----------------+ | AuthID | AuthorFirstName | AuthorMiddleName | AuthorLastName | +--------+-----------------+------------------+----------------+ | 1006 | Henry | S. | Thompson | | 1007 | Jason | Carol | Oak | | 1008 | James | NULL | Elk | | 1009 | Tom | M | Ride | | 1010 | Jack | K | Ken | | 1011 | Mary | G. | Lee | | 1012 | Annie | NULL | Watts | | 1013 | Alan | NULL | Wang | | 1014 | Nelson | NULL | Yin | +--------+-----------------+------------------+----------------+ 9 rows in set (0.00 sec)
- /
Drop table Articles; Drop table Authors; Drop table AuthorArticle;
CREATE TABLE Articles (
ArticleID SMALLINT NOT NULL PRIMARY KEY, ArticleTitle VARCHAR(60) NOT NULL, Copyright YEAR NOT NULL
) ENGINE=INNODB;
INSERT INTO Articles VALUES (12786, "How write a paper", 1934),
(13331, "Publish a paper", 1919),
(14356, "Sell a paper", 1966),
(15729, "Buy a paper", 1932),
(16284, "Conferences", 1996),
(17695, "Journal", 1980),
(19264, "Information", 1992),
(19354, "AI", 1993);
CREATE TABLE Authors (
AuthID SMALLINT NOT NULL PRIMARY KEY, AuthorFirstName VARCHAR(20), AuthorMiddleName VARCHAR(20), AuthorLastName VARCHAR(20)
) ENGINE=INNODB;
INSERT INTO Authors VALUES (1006, "Henry", "S.", "Thompson"),
(1007, "Jason", "Carol", "Oak"),
(1008, "James", NULL, "Elk"),
(1009, "Tom", "M", "Ride"),
(1010, "Jack", "K", "Ken"),
(1011, "Mary", "G.", "Lee"),
(1012, "Annie", NULL, "Peng"),
(1013, "Alan", NULL, "Wang"),
(1014, "Nelson", NULL, "Yin");
CREATE TABLE AuthorArticle (
AuthID SMALLINT NOT NULL, ArticleID SMALLINT NOT NULL, PRIMARY KEY (AuthID, ArticleID), FOREIGN KEY (AuthID) REFERENCES Authors (AuthID), FOREIGN KEY (ArticleID) REFERENCES Articles (ArticleID)
) ENGINE=INNODB;
INSERT INTO AuthorArticle VALUES (1006, 14356),
(1008, 15729),
(1009, 12786),
(1010, 17695),
(1011, 15729),
(1012, 19264),
(1012, 19354),
(1014, 16284);
select * from Authors;
UPDATE Authors CROSS JOIN AuthorArticle USING (AuthID)
CROSS JOIN Articles USING (ArticleID)
SET AuthorLastName="Watts" WHERE ArticleTitle="Information"; select * from Authors;
</source>
JOIN two tables in update command
<source lang="sql">
/* mysql> mysql> select * from Authors; +--------+-----------------+------------------+----------------+ | AuthID | AuthorFirstName | AuthorMiddleName | AuthorLastName | +--------+-----------------+------------------+----------------+ | 1006 | Henry | S. | Thompson | | 1007 | Jason | Carol | Oak | | 1008 | James | NULL | Elk | | 1009 | Tom | M | Ride | | 1010 | Jack | K | Ken | | 1011 | Mary | G. | Lee | | 1012 | Annie | NULL | Wats | | 1013 | Alan | NULL | Wang | | 1014 | Nelson | NULL | Yin | +--------+-----------------+------------------+----------------+ 9 rows in set (0.01 sec) mysql> mysql> select * from Authors; +--------+-----------------+------------------+----------------+ | AuthID | AuthorFirstName | AuthorMiddleName | AuthorLastName | +--------+-----------------+------------------+----------------+ | 1006 | Henry | S. | Thompson | | 1007 | Jason | Carol | Oak | | 1008 | James | NULL | Elk | | 1009 | Tom | M | Ride | | 1010 | Jack | K | Ken | | 1011 | Mary | G. | Lee | | 1012 | Annie | NULL | Wats | | 1013 | Alan | NULL | Wang | | 1014 | Nelson | NULL | Yin | +--------+-----------------+------------------+----------------+ 9 rows in set (0.01 sec) mysql>
- /
Drop table Articles; Drop table Authors; Drop table AuthorArticle;
CREATE TABLE Articles (
ArticleID SMALLINT NOT NULL PRIMARY KEY, ArticleTitle VARCHAR(60) NOT NULL, Copyright YEAR NOT NULL
) ENGINE=INNODB;
INSERT INTO Articles VALUES (12786, "How write a paper", 1934),
(13331, "Publish a paper", 1919),
(14356, "Sell a paper", 1966),
(15729, "Buy a paper", 1932),
(16284, "Conferences", 1996),
(17695, "Journal", 1980),
(19264, "Information", 1992),
(19354, "AI", 1993);
CREATE TABLE Authors (
AuthID SMALLINT NOT NULL PRIMARY KEY, AuthorFirstName VARCHAR(20), AuthorMiddleName VARCHAR(20), AuthorLastName VARCHAR(20)
) ENGINE=INNODB;
INSERT INTO Authors VALUES (1006, "Henry", "S.", "Thompson"),
(1007, "Jason", "Carol", "Oak"),
(1008, "James", NULL, "Elk"),
(1009, "Tom", "M", "Ride"),
(1010, "Jack", "K", "Ken"),
(1011, "Mary", "G.", "Lee"),
(1012, "Annie", NULL, "Peng"),
(1013, "Alan", NULL, "Wang"),
(1014, "Nelson", NULL, "Yin");
CREATE TABLE AuthorArticle (
AuthID SMALLINT NOT NULL, ArticleID SMALLINT NOT NULL, PRIMARY KEY (AuthID, ArticleID), FOREIGN KEY (AuthID) REFERENCES Authors (AuthID), FOREIGN KEY (ArticleID) REFERENCES Articles (ArticleID)
) ENGINE=INNODB;
INSERT INTO AuthorArticle VALUES (1006, 14356),
(1008, 15729),
(1009, 12786),
(1010, 17695),
(1011, 15729),
(1012, 19264),
(1012, 19354),
(1014, 16284);
select * from Authors;
UPDATE Authors AS a, AuthorArticle AS ab, Articles AS b SET AuthorLastName="Wats" WHERE a.AuthID=ab.AuthID AND ab.ArticleID=b.ArticleID
AND ArticleTitle="AI";
select * from Authors;
</source>
