MySQL Tutorial/Table Join/RIGHT JOIN

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RIGHT JOIN

A RIGHT JOIN is a variation of Left JOIN where all the data on the RIGHT side of the join (the second table) is returned regardless of the presence of data from the first table.



   <source lang="sql">

mysql> mysql> mysql> CREATE TABLE Employee( 

   ->     id            int,
   ->     first_name    VARCHAR(15),
   ->     last_name     VARCHAR(15),
   ->     start_date    DATE,
   ->     end_date      DATE,
   ->     salary        FLOAT(8,2),
   ->     city          VARCHAR(10),
   ->     description   VARCHAR(15)
   -> );

Query OK, 0 rows affected (0.01 sec) mysql> mysql> create table job ( 

   ->   id         int,
   ->   title      VARCHAR(20)
   -> );

Query OK, 0 rows affected (0.03 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->              values (1,"Jason",    "Martin",  "19960725",  "20060725", 1234.56, "Toronto",  "Programmer");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->               values(2,"Alison",   "Mathews",  "19760321", "19860221", 6661.78, "Vancouver","Tester");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->               values(3,"James",    "Smith",    "19781212", "19900315", 6544.78, "Vancouver","Tester");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->               values(4,"Celia",    "Rice",     "19821024", "19990421", 2344.78, "Vancouver","Manager");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->               values(5,"Robert",   "Black",    "19840115", "19980808", 2334.78, "Vancouver","Tester");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->               values(6,"Linda",    "Green",    "19870730", "19960104", 4322.78,"New York",  "Tester");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->               values(7,"David",    "Larry",    "19901231", "19980212", 7897.78,"New York",  "Manager");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->               values(8,"James",    "Cat",     "19960917",  "20020415", 1232.78,"Vancouver", "Tester");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into job (id, title) values (1,"Tester"); Query OK, 1 row affected (0.00 sec) mysql> insert into job (id, title) values (2,"Accountant"); Query OK, 1 row affected (0.00 sec) mysql> insert into job (id, title) values (3,"Developer"); Query OK, 1 row affected (0.00 sec) mysql> insert into job (id, title) values (4,"COder"); Query OK, 1 row affected (0.00 sec) mysql> insert into job (id, title) values (5,"Director"); Query OK, 1 row affected (0.00 sec) mysql> insert into job (id, title) values (6,"Mediator"); Query OK, 1 row affected (0.00 sec) mysql> insert into job (id, title) values (7,"Proffessor"); Query OK, 1 row affected (0.00 sec) mysql> insert into job (id, title) values (8,"Programmer"); Query OK, 1 row affected (0.01 sec) mysql> insert into job (id, title) values (9,"Developer"); Query OK, 1 row affected (0.00 sec) mysql> mysql> select * from job; +------+------------+ | id | title | +------+------------+ | 1 | Tester | | 2 | Accountant | | 3 | Developer | | 4 | COder | | 5 | Director | | 6 | Mediator | | 7 | Proffessor | | 8 | Programmer | | 9 | Developer | +------+------------+ 9 rows in set (0.00 sec) mysql> select * from Employee; +------+------------+-----------+------------+------------+---------+-----------+-------------+ | id | first_name | last_name | start_date | end_date | salary | city | description | +------+------------+-----------+------------+------------+---------+-----------+-------------+ | 1 | Jason | Martin | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto | Programmer | | 2 | Alison | Mathews | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester | | 3 | James | Smith | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester | | 4 | Celia | Rice | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager | | 5 | Robert | Black | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester | | 6 | Linda | Green | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester | | 7 | David | Larry | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager | | 8 | James | Cat | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester | +------+------------+-----------+------------+------------+---------+-----------+-------------+ 8 rows in set (0.00 sec) mysql> mysql> mysql> SELECT employee.first_name, employee.city, job.title 

   -> FROM employee
   -> RIGHT JOIN job
   -> ON employee.ID = job.ID;

+------------+-----------+------------+ | first_name | city | title | +------------+-----------+------------+ | Jason | Toronto | Tester | | Alison | Vancouver | Accountant | | James | Vancouver | Developer | | Celia | Vancouver | COder | | Robert | Vancouver | Director | | Linda | New York | Mediator | | David | New York | Proffessor | | James | Vancouver | Programmer | | NULL | NULL | Developer | +------------+-----------+------------+ 9 rows in set (0.00 sec) mysql> mysql> mysql> drop table job; Query OK, 0 rows affected (0.00 sec) mysql> drop table Employee; Query OK, 0 rows affected (0.00 sec) mysql> mysql></source>


Right Join more than two tables

   <source lang="sql">

mysql> mysql> mysql> CREATE TABLE Employee( 

   ->     id            int,
   ->     first_name    VARCHAR(15),
   ->     last_name     VARCHAR(15),
   ->     start_date    DATE,
   ->     end_date      DATE,
   ->     salary        FLOAT(8,2),
   ->     city          VARCHAR(10),
   ->     description   VARCHAR(15)
   -> );

Query OK, 0 rows affected (0.05 sec) mysql> mysql> create table job ( 

   ->   id         int,
   ->   title      VARCHAR(20)
   -> );

Query OK, 0 rows affected (0.05 sec) mysql> mysql> mysql> create table duty ( 

   ->   id         int,
   ->   task       VARCHAR(20)
   -> );

Query OK, 0 rows affected (0.05 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->              values (1,"Jason",    "Martin",  "19960725",  "20060725", 1234.56, "Toronto",  "Programmer");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->               values(2,"Alison",   "Mathews",  "19760321", "19860221", 6661.78, "Vancouver","Tester");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->               values(3,"James",    "Smith",    "19781212", "19900315", 6544.78, "Vancouver","Tester");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->               values(4,"Celia",    "Rice",     "19821024", "19990421", 2344.78, "Vancouver","Manager");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->               values(5,"Robert",   "Black",    "19840115", "19980808", 2334.78, "Vancouver","Tester");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->               values(6,"Linda",    "Green",    "19870730", "19960104", 4322.78,"New York",  "Tester");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->               values(7,"David",    "Larry",    "19901231", "19980212", 7897.78,"New York",  "Manager");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description) 

   ->               values(8,"James",    "Cat",     "19960917",  "20020415", 1232.78,"Vancouver", "Tester");

Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into job (id, title) values (1,"Tester"); Query OK, 1 row affected (0.00 sec) mysql> insert into job (id, title) values (2,"Accountant"); Query OK, 1 row affected (0.00 sec) mysql> insert into job (id, title) values (3,"Developer"); Query OK, 1 row affected (0.00 sec) mysql> insert into job (id, title) values (4,"Coder"); Query OK, 1 row affected (0.00 sec) mysql> insert into job (id, title) values (5,"Director"); Query OK, 1 row affected (0.02 sec) mysql> insert into job (id, title) values (6,"Mediator"); Query OK, 1 row affected (0.00 sec) mysql> insert into job (id, title) values (7,"Proffessor"); Query OK, 1 row affected (0.00 sec) mysql> insert into job (id, title) values (8,"Programmer"); Query OK, 1 row affected (0.00 sec) mysql> insert into job (id, title) values (9,"Developer"); Query OK, 1 row affected (0.00 sec) mysql> mysql> insert into duty (id, task) values (1,"Test"); Query OK, 1 row affected (0.00 sec) mysql> insert into duty (id, task) values (2,"Calculate"); Query OK, 1 row affected (0.00 sec) mysql> insert into duty (id, task) values (3,"Program"); Query OK, 1 row affected (0.00 sec) mysql> insert into duty (id, task) values (4,"Test"); Query OK, 1 row affected (0.00 sec) mysql> insert into duty (id, task) values (5,"Manage"); Query OK, 1 row affected (0.00 sec) mysql> insert into duty (id, task) values (6,"Talk"); Query OK, 1 row affected (0.00 sec) mysql> insert into duty (id, task) values (7,"Speak"); Query OK, 1 row affected (0.00 sec) mysql> insert into duty (id, task) values (8,"Shout"); Query OK, 1 row affected (0.00 sec) mysql> insert into duty (id, task) values (9,"Walk"); Query OK, 1 row affected (0.00 sec) mysql> mysql> select * from job; +------+------------+ | id | title | +------+------------+ | 1 | Tester | | 2 | Accountant | | 3 | Developer | | 4 | Coder | | 5 | Director | | 6 | Mediator | | 7 | Proffessor | | 8 | Programmer | | 9 | Developer | +------+------------+ 9 rows in set (0.00 sec) mysql> select * from Employee; +------+------------+-----------+------------+------------+---------+-----------+-------------+ | id | first_name | last_name | start_date | end_date | salary | city | description | +------+------------+-----------+------------+------------+---------+-----------+-------------+ | 1 | Jason | Martin | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto | Programmer | | 2 | Alison | Mathews | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester | | 3 | James | Smith | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester | | 4 | Celia | Rice | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager | | 5 | Robert | Black | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester | | 6 | Linda | Green | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester | | 7 | David | Larry | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager | | 8 | James | Cat | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester | +------+------------+-----------+------------+------------+---------+-----------+-------------+ 8 rows in set (0.00 sec) mysql> select * from duty; +------+-----------+ | id | task | +------+-----------+ | 1 | Test | | 2 | Calculate | | 3 | Program | | 4 | Test | | 5 | Manage | | 6 | Talk | | 7 | Speak | | 8 | Shout | | 9 | Walk | +------+-----------+ 9 rows in set (0.00 sec) mysql> mysql> mysql> mysql> mysql> SELECT employee.first_name, job.title, duty.task 

   -> FROM employee
   -> RIGHT JOIN job
   -> ON employee.ID = job.ID
   -> RIGHT JOIN duty
   -> ON employee.ID = duty.ID;

+------------+------------+-----------+ | first_name | title | task | +------------+------------+-----------+ | Jason | Tester | Test | | Alison | Accountant | Calculate | | James | Developer | Program | | Celia | Coder | Test | | Robert | Director | Manage | | Linda | Mediator | Talk | | David | Proffessor | Speak | | James | Programmer | Shout | | NULL | NULL | Walk | +------------+------------+-----------+ 9 rows in set (0.00 sec) mysql> mysql> mysql> drop table duty; Query OK, 0 rows affected (0.01 sec) mysql> drop table job; Query OK, 0 rows affected (0.00 sec) mysql> drop table Employee; Query OK, 0 rows affected (0.00 sec) mysql></source>


Three-Table RIGHT JOIN

   <source lang="sql">

mysql> mysql> mysql> CREATE TABLE Books( 

   ->    BookID SMALLINT NOT NULL PRIMARY KEY,
   ->    BookTitle VARCHAR(60) NOT NULL,
   ->    Copyright YEAR NOT NULL
   -> )
   -> ENGINE=INNODB;

Query OK, 0 rows affected (0.05 sec) mysql> mysql> mysql> INSERT INTO Books VALUES (12786, "Java", 1934), 

   ->                          (13331, "MySQL",          1919),
   ->                          (14356, "PHP",            1966),
   ->                          (15729, "PERL",           1932),
   ->                          (16284, "Oracle",         1996),
   ->                          (17695, "Pl/SQL",         1980),
   ->                          (19264, "JavaScript",     1992),
   ->                          (19354, "www.sqle.ru", 1993);

Query OK, 8 rows affected (0.03 sec) Records: 8 Duplicates: 0 Warnings: 0 mysql> mysql> mysql> CREATE TABLE Authors( 

   ->    AuthID SMALLINT NOT NULL PRIMARY KEY,
   ->    AuthFN VARCHAR(20),
   ->    AuthMN VARCHAR(20),
   ->    AuthLN VARCHAR(20)
   -> )
   -> ENGINE=INNODB;

Query OK, 0 rows affected (0.05 sec) mysql> mysql> mysql> INSERT INTO Authors VALUES (1006, "H", "S.", "T"), 

   ->                            (1007, "J", "C",  "O"),
   ->                            (1008, "B", NULL, "E"),
   ->                            (1009, "R", "M",  "R"),
   ->                            (1010, "J", "K",  "T"),
   ->                            (1011, "J", "G.", "N"),
   ->                            (1012, "A", NULL, "P"),
   ->                            (1013, "A", NULL, "W"),
   ->                            (1014, "N", NULL, "A");

Query OK, 9 rows affected (0.01 sec) Records: 9 Duplicates: 0 Warnings: 0 mysql> mysql> mysql> CREATE TABLE AuthorBook( 

   ->    AuthID SMALLINT NOT NULL,
   ->    BookID SMALLINT NOT NULL,
   ->    PRIMARY KEY (AuthID, BookID),
   ->    FOREIGN KEY (AuthID) REFERENCES Authors (AuthID),
   ->    FOREIGN KEY (BookID) REFERENCES Books (BookID)
   -> )
   -> ENGINE=INNODB;

Query OK, 0 rows affected (0.09 sec) mysql> mysql> mysql> INSERT INTO AuthorBook VALUES (1006, 14356), 

   ->                               (1008, 15729),
   ->                               (1009, 12786),
   ->                               (1010, 17695),
   ->                               (1011, 15729),
   ->                               (1012, 19264),
   ->                               (1012, 19354),
   ->                               (1014, 16284);

Query OK, 8 rows affected (0.03 sec) Records: 8 Duplicates: 0 Warnings: 0 mysql> mysql> mysql> select * from Authors; +--------+--------+--------+--------+ | AuthID | AuthFN | AuthMN | AuthLN | +--------+--------+--------+--------+ | 1006 | H | S. | T | | 1007 | J | C | O | | 1008 | B | NULL | E | | 1009 | R | M | R | | 1010 | J | K | T | | 1011 | J | G. | N | | 1012 | A | NULL | P | | 1013 | A | NULL | W | | 1014 | N | NULL | A | +--------+--------+--------+--------+ 9 rows in set (0.00 sec) mysql> select * from Books; +--------+----------------+-----------+ | BookID | BookTitle | Copyright | +--------+----------------+-----------+ | 12786 | Java | 1934 | | 13331 | MySQL | 1919 | | 14356 | PHP | 1966 | | 15729 | PERL | 1932 | | 16284 | Oracle | 1996 | | 17695 | Pl/SQL | 1980 | | 19264 | JavaScript | 1992 | | 19354 | www.sqle.ru | 1993 | +--------+----------------+-----------+ 8 rows in set (0.00 sec) mysql> select * from AuthorBook; +--------+--------+ | AuthID | BookID | +--------+--------+ | 1009 | 12786 | | 1006 | 14356 | | 1008 | 15729 | | 1011 | 15729 | | 1014 | 16284 | | 1010 | 17695 | | 1012 | 19264 | | 1012 | 19354 | +--------+--------+ 8 rows in set (0.00 sec) mysql> mysql> mysql> SELECT BookTitle, Copyright, CONCAT_WS(" ", AuthFN, AuthMN, AuthLN) AS Author 

   -> FROM Books AS b RIGHT JOIN AuthorBook AS ab ON b.BookID=ab.BookID
   ->    RIGHT JOIN Authors AS a ON ab.AuthID=a.AuthID
   -> ORDER BY BookTitle;

+----------------+-----------+--------+ | BookTitle | Copyright | Author | +----------------+-----------+--------+ | NULL | NULL | A W | | NULL | NULL | J C O | | Java | 1934 | R M R | | JavaScript | 1992 | A P | | Oracle | 1996 | N A | | PERL | 1932 | B E | | PERL | 1932 | J G. N | | PHP | 1966 | H S. T | | Pl/SQL | 1980 | J K T | | www.sqle.ru | 1993 | A P | +----------------+-----------+--------+ 10 rows in set (0.00 sec) mysql> mysql> drop table AuthorBook; Query OK, 0 rows affected (0.02 sec) mysql> drop table Books; Query OK, 0 rows affected (0.05 sec) mysql> drop table Authors; Query OK, 0 rows affected (0.03 sec)</source>

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