Using key word USING, in which the common linking field is specified. : Using « Join « SQL / MySQL

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SQL / MySQL » Join » Using 
Using key word USING, in which the common linking field is specified.
      
mysql>
mysql>
mysql> CREATE TABLE titles (
    ->   titleID int(11),
    ->   title varchar(100),
    ->   subtitle varchar(100),
    ->   edition tinyint(4),
    ->   publID int(11),
    ->   catID int(11),
    ->   langID int(11),
    ->   year int(11),
    ->   isbn varchar(20),
    ->   comment varchar(255),
    ->   ts timestamp,
    ->   authors varchar(255),
    ->   PRIMARY KEY  (titleID)
    -> );
Query OK, rows affected (0.00 sec)

mysql>
mysql>
mysql>
mysql> INSERT INTO titles VALUES (1,'Linux','Installation',5,1,57,2,2000,NULL,NULL,'2005-02-28 13:34:21','Michael'),
    ->                           (2,'Excel',NULL,NULL,2,3,NULL,2000,NULL,NULL,'2005-02-28 13:34:22','David'),
    ->                           (3,'XML',NULL,NULL,1,2,NULL,1997,NULL,NULL,'2005-02-28 13:34:22','Edwards'),
    ->                           (4,'PHP',NULL,NULL,3,6,NULL,2000,NULL,NULL,'2005-02-28 13:34:22','Tom'),
    ->                           (5,'MySQL','',0,3,34,NULL,2000,'','','2005-02-28 13:34:22','Paul'),
    ->                           (6,'Java',NULL,NULL,4,34,NULL,1999,NULL,NULL,'2005-02-28 13:34:22','Tim');
Query OK, rows affected (0.00 sec)
Records: 6  Duplicates: 0  Warnings: 0

mysql>
mysql> CREATE TABLE publishers (
    ->   publID int(11NOT NULL auto_increment,
    ->   publName varchar(60collate latin1_german1_ci NOT NULL default '',
    ->   ts timestamp NOT NULL default CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP,
    ->   PRIMARY KEY  (publID),
    ->   KEY publName (publName)
    -> ENGINE=InnoDB DEFAULT CHARSET=latin1 COLLATE=latin1_german1_ci;
Query OK, rows affected (0.01 sec)

mysql>
mysql>
mysql> INSERT INTO publishers VALUES (1,'A','2004-12-02 18:36:58'),
    ->                                 (2,'Apress','2004-12-02 18:36:58'),
    ->                                 (3,'New Riders','2004-12-02 18:36:58'),
    ->                                 (4,'O\'Reilly & Associates','2004-12-02 18:36:58'),
    ->                                 (5,'Hanser','2004-12-02 18:36:58');
Query OK, rows affected (0.00 sec)
Records: 5  Duplicates: 0  Warnings: 0

However, this variant assumes that the linking field (in this case publIDhas the same name in
both tables. That is, of course, not always the case:
mysql>
mysql> SELECT title, publName FROM titles LEFT JOIN publishers USING (publID);
+-------+-----------------------+
| title | publName              |
+-------+-----------------------+
| Linux | A                     |
| Excel | Apress                |
| XML   | A                     |
| PHP   | New Riders            |
| MySQL | New Riders            |
| Java  | O'Reilly & Associates |
+-------+-----------------------+
rows in set (0.00 sec)

mysql>
mysql>
mysql>
mysql> drop table titles;
Query OK, rows affected (0.00 sec)

mysql> drop table publishers;
Query OK, rows affected (0.00 sec)

   
    
    
    
    
    
  
Related examples in the same category
1.Using temp table during table join
2.Using a Join to Fill in Holes in a List
3.Produce the same results by using a USING clause to qualify the join
4.Specify the necessary join conditions in an ON or USING clause.
5.Natural Joins and the USING Keyword
6.Create the same report using the JOIN function in the following command.
7.Using function in where clause during table joining
8.Using table alias in table join
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