MySQL Tutorial/Table Join/RIGHT JOIN

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Версия от 09:53, 26 мая 2010; Admin (обсуждение | вклад) (1 версия)
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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.



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>


Right Join more than two tables

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>


Three-Table RIGHT JOIN

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)
Источник — «http://sqle.ru/index.php?title=MySQL_Tutorial/Table_Join/RIGHT_JOIN&oldid=821»