Oracle PL/SQL Tutorial/Table Joins/Outer Joins Left Right — различия между версиями

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Текущая версия на 10:03, 26 мая 2010

An Example of a Left Outer Join 1

SQL>
SQL>
SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    EMPNO         NUMBER(3),
  3    ENAME         VARCHAR2(15 BYTE),
  4    HIREDATE      DATE,
  5    ORIG_SALARY   NUMBER(6),
  6    CURR_SALARY   NUMBER(6),
  7    REGION        VARCHAR2(1 BYTE)
  8  )
  9  /
Table created.
SQL>
SQL> create table job (
  2    EMPNO         NUMBER(3),
  3    jobtitle      VARCHAR2(20 BYTE)
  4  )
  5  /
Table created.
SQL>
SQL> insert into job (EMPNO, Jobtitle) values (1,"Tester");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (2,"Accountant");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (3,"Developer");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (9,"Developer");
1 row created.
SQL>
SQL>
SQL> -- prepare data
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (1,      "Jason", to_date("19960725","YYYYMMDD"), 1234,              8767,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (2,      "John",  to_date("19970715","YYYYMMDD"), 2341,              3456,         "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (3,      "Joe",   to_date("19860125","YYYYMMDD"), 4321,              5654,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (4,      "Tom",   to_date("20060913","YYYYMMDD"), 2413,              6787,         "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (5,      "Jane",  to_date("20050417","YYYYMMDD"), 7654,              4345,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (6,      "James", to_date("20040718","YYYYMMDD"), 5679,              6546,         "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (7,      "Jodd",  to_date("20030720","YYYYMMDD"), 5438,              7658,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (8,      "Joke",  to_date("20020101","YYYYMMDD"), 8765,              4543,         "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (9,      "Jack",  to_date("20010829","YYYYMMDD"), 7896,              1232,         "E")
  3  /
1 row created.
SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /
     EMPNO ENAME           HIREDATE  ORIG_SALARY CURR_SALARY R
---------- --------------- --------- ----------- ----------- -
         1 Jason           25-JUL-96        1234        8767 E
         2 John            15-JUL-97        2341        3456 W
         3 Joe             25-JAN-86        4321        5654 E
         4 Tom             13-SEP-06        2413        6787 W
         5 Jane            17-APR-05        7654        4345 E
         6 James           18-JUL-04        5679        6546 W
         7 Jodd            20-JUL-03        5438        7658 E
         8 Joke            01-JAN-02        8765        4543 W
         9 Jack            29-AUG-01        7896        1232 E
9 rows selected.
SQL> select * from job
  2  /
     EMPNO JOBTITLE
---------- --------------------
         1 Tester
         2 Accountant
         3 Developer
         9 Developer
SQL>
SQL> SELECT e.ename, j.jobtitle FROM employee e, job j WHERE e.empno = j.empno (+);
ENAME           JOBTITLE
--------------- --------------------
Jason           Tester
John            Accountant
Joe             Developer
Jack            Developer
Jane
Joke
James
Jodd
Tom
9 rows selected.
SQL>
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL> drop table job
  2  /
Table dropped.


An Example of a Left Outer Join 2

SQL>
SQL>
SQL>
SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    EMPNO         NUMBER(3),
  3    ENAME         VARCHAR2(15 BYTE),
  4    HIREDATE      DATE,
  5    ORIG_SALARY   NUMBER(6),
  6    CURR_SALARY   NUMBER(6),
  7    REGION        VARCHAR2(1 BYTE)
  8  )
  9  /
Table created.
SQL>
SQL> create table job (
  2    EMPNO         NUMBER(3),
  3    jobtitle      VARCHAR2(20 BYTE)
  4  )
  5  /
Table created.
SQL>
SQL> insert into job (EMPNO, Jobtitle) values (1,"Tester");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (2,"Accountant");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (3,"Developer");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (4,"COder");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (5,"Director");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (6,"Mediator");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (7,"Proffessor");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (8,"Programmer");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (9,"Developer");
1 row created.
SQL>
SQL>
SQL> -- prepare data
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (1,      "Jason", to_date("19960725","YYYYMMDD"), 1234,              8767,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (2,      "John",  to_date("19970715","YYYYMMDD"), 2341,              3456,         "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (3,      "Joe",   to_date("19860125","YYYYMMDD"), 4321,              5654,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (9,      "Jack",  to_date("20010829","YYYYMMDD"), 7896,              1232,         "E")
  3  /
1 row created.
SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /
     EMPNO ENAME           HIREDATE  ORIG_SALARY CURR_SALARY R
---------- --------------- --------- ----------- ----------- -
         1 Jason           25-JUL-96        1234        8767 E
         2 John            15-JUL-97        2341        3456 W
         3 Joe             25-JAN-86        4321        5654 E
         9 Jack            29-AUG-01        7896        1232 E
SQL> select * from job
  2  /
     EMPNO JOBTITLE
---------- --------------------
         1 Tester
         2 Accountant
         3 Developer
         4 COder
         5 Director
         6 Mediator
         7 Proffessor
         8 Programmer
         9 Developer
9 rows selected.
SQL>
SQL>
SQL> SELECT e.ename, j.jobtitle FROM employee e, job j WHERE e.empno = j.empno (+);
ENAME           JOBTITLE
--------------- --------------------
Jason           Tester
John            Accountant
Joe             Developer
Jack            Developer
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL> drop table job
  2  /
Table dropped.
SQL>


An Example of a Right Outer Join 1

SQL>
SQL>
SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    EMPNO         NUMBER(3),
  3    ENAME         VARCHAR2(15 BYTE),
  4    HIREDATE      DATE,
  5    ORIG_SALARY   NUMBER(6),
  6    CURR_SALARY   NUMBER(6),
  7    REGION        VARCHAR2(1 BYTE)
  8  )
  9  /
Table created.
SQL>
SQL> create table job (
  2    EMPNO         NUMBER(3),
  3    jobtitle      VARCHAR2(20 BYTE)
  4  )
  5  /
Table created.
SQL>
SQL> insert into job (EMPNO, Jobtitle) values (1,"Tester");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (2,"Accountant");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (3,"Developer");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (4,"COder");
1 row created.
SQL>
SQL> insert into job (EMPNO, Jobtitle) values (9,"Developer");
1 row created.
SQL>
SQL>
SQL> -- prepare data
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (1,      "Jason", to_date("19960725","YYYYMMDD"), 1234,              8767,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (2,      "John",  to_date("19970715","YYYYMMDD"), 2341,              3456,         "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (3,      "Joe",   to_date("19860125","YYYYMMDD"), 4321,              5654,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (4,      "Tom",   to_date("20060913","YYYYMMDD"), 2413,              6787,         "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (5,      "Jane",  to_date("20050417","YYYYMMDD"), 7654,              4345,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (6,      "James", to_date("20040718","YYYYMMDD"), 5679,              6546,         "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (7,      "Jodd",  to_date("20030720","YYYYMMDD"), 5438,              7658,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (8,      "Joke",  to_date("20020101","YYYYMMDD"), 8765,              4543,         "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (9,      "Jack",  to_date("20010829","YYYYMMDD"), 7896,              1232,         "E")
  3  /
1 row created.
SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /
     EMPNO ENAME           HIREDATE  ORIG_SALARY CURR_SALARY R
---------- --------------- --------- ----------- ----------- -
         1 Jason           25-JUL-96        1234        8767 E
         2 John            15-JUL-97        2341        3456 W
         3 Joe             25-JAN-86        4321        5654 E
         4 Tom             13-SEP-06        2413        6787 W
         5 Jane            17-APR-05        7654        4345 E
         6 James           18-JUL-04        5679        6546 W
         7 Jodd            20-JUL-03        5438        7658 E
         8 Joke            01-JAN-02        8765        4543 W
         9 Jack            29-AUG-01        7896        1232 E
9 rows selected.
SQL> select * from job
  2  /
     EMPNO JOBTITLE
---------- --------------------
         1 Tester
         2 Accountant
         3 Developer
         4 COder
         9 Developer
SQL>
SQL>
SQL> SELECT e.ename, j.jobtitle FROM employee e, job j WHERE e.empno (+) = j.empno ;
ENAME           JOBTITLE
--------------- --------------------
Jason           Tester
John            Accountant
Joe             Developer
Tom             COder
Jack            Developer
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL> drop table job
  2  /
Table dropped.


An Example of a Right Outer Join 2

SQL>
SQL>
SQL>
SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    EMPNO         NUMBER(3),
  3    ENAME         VARCHAR2(15 BYTE),
  4    HIREDATE      DATE,
  5    ORIG_SALARY   NUMBER(6),
  6    CURR_SALARY   NUMBER(6),
  7    REGION        VARCHAR2(1 BYTE)
  8  )
  9  /
Table created.
SQL>
SQL> create table job (
  2    EMPNO         NUMBER(3),
  3    jobtitle      VARCHAR2(20 BYTE)
  4  )
  5  /
Table created.
SQL>
SQL> insert into job (EMPNO, Jobtitle) values (1,"Tester");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (2,"Accountant");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (3,"Developer");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (4,"COder");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (5,"Director");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (6,"Mediator");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (7,"Proffessor");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (8,"Programmer");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (9,"Developer");
1 row created.
SQL>
SQL>
SQL> -- prepare data
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (1,      "Jason", to_date("19960725","YYYYMMDD"), 1234,              8767,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (2,      "John",  to_date("19970715","YYYYMMDD"), 2341,              3456,         "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (3,      "Joe",   to_date("19860125","YYYYMMDD"), 4321,              5654,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (4,      "Tom",   to_date("20060913","YYYYMMDD"), 2413,              6787,         "W")
  3  /
1 row created.
SQL>
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (9,      "Jack",  to_date("20010829","YYYYMMDD"), 7896,              1232,         "E")
  3  /
1 row created.
SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /
     EMPNO ENAME           HIREDATE  ORIG_SALARY CURR_SALARY R
---------- --------------- --------- ----------- ----------- -
         1 Jason           25-JUL-96        1234        8767 E
         2 John            15-JUL-97        2341        3456 W
         3 Joe             25-JAN-86        4321        5654 E
         4 Tom             13-SEP-06        2413        6787 W
         9 Jack            29-AUG-01        7896        1232 E
SQL> select * from job
  2  /
     EMPNO JOBTITLE
---------- --------------------
         1 Tester
         2 Accountant
         3 Developer
         4 COder
         5 Director
         6 Mediator
         7 Proffessor
         8 Programmer
         9 Developer
9 rows selected.
SQL>
SQL>
SQL> SELECT e.ename, j.jobtitle FROM employee e, job j WHERE e.empno (+) = j.empno ;
ENAME           JOBTITLE
--------------- --------------------
Jason           Tester
John            Accountant
Joe             Developer
Tom             COder
Jack            Developer
                Director
                Programmer
                Mediator
                Proffessor
9 rows selected.
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL> drop table job
  2  /
Table dropped.


Example outer join with (+)

SQL>
SQL> CREATE TABLE EMP (EMPNO NUMBER(4) NOT NULL,
  2                    ENAME VARCHAR2(10),
  3                    JOB VARCHAR2(9),
  4                    MGR NUMBER(4),
  5                    HIREDATE DATE,
  6                    SAL NUMBER(7, 2),
  7                    COMM NUMBER(7, 2),
  8                    DEPTNO NUMBER(2));
Table created.
SQL>
SQL> INSERT INTO EMP VALUES (7369, "SMITH", "CLERK",    7902, TO_DATE("17-DEC-1980", "DD-MON-YYYY"), 800, NULL, 20);
1 row created.
SQL> INSERT INTO EMP VALUES (7499, "ALLEN", "SALESMAN", 7698, TO_DATE("20-FEB-1981", "DD-MON-YYYY"), 1600, 300, 30);
1 row created.
SQL> INSERT INTO EMP VALUES (7521, "WARD",  "SALESMAN", 7698, TO_DATE("22-FEB-1981", "DD-MON-YYYY"), 1250, 500, 30);
1 row created.
SQL> INSERT INTO EMP VALUES (7566, "JONES", "MANAGER",  7839, TO_DATE("2-APR-1981",  "DD-MON-YYYY"), 2975, NULL, 20);
1 row created.
SQL> INSERT INTO EMP VALUES (7654, "MARTIN", "SALESMAN", 7698,TO_DATE("28-SEP-1981", "DD-MON-YYYY"), 1250, 1400, 30);
1 row created.
SQL> INSERT INTO EMP VALUES (7698, "BLAKE", "MANAGER", 7839,TO_DATE("1-MAY-1981", "DD-MON-YYYY"), 2850, NULL, 30);
1 row created.
SQL> INSERT INTO EMP VALUES (7782, "CLARK", "MANAGER", 7839,TO_DATE("9-JUN-1981", "DD-MON-YYYY"), 2450, NULL, 10);
1 row created.
SQL> INSERT INTO EMP VALUES (7788, "SCOTT", "ANALYST", 7566,TO_DATE("09-DEC-1982", "DD-MON-YYYY"), 3000, NULL, 20);
1 row created.
SQL> INSERT INTO EMP VALUES (7839, "KING", "PRESIDENT", NULL,TO_DATE("17-NOV-1981", "DD-MON-YYYY"), 5000, NULL, 10);
1 row created.
SQL> INSERT INTO EMP VALUES (7844, "TURNER", "SALESMAN", 7698,TO_DATE("8-SEP-1981", "DD-MON-YYYY"), 1500, 0, 30);
1 row created.
SQL> INSERT INTO EMP VALUES (7876, "ADAMS", "CLERK", 7788,TO_DATE("12-JAN-1983", "DD-MON-YYYY"), 1100, NULL, 20);
1 row created.
SQL> INSERT INTO EMP VALUES (7900, "JAMES", "CLERK", 7698,TO_DATE("3-DEC-1981", "DD-MON-YYYY"), 950, NULL, 30);
1 row created.
SQL> INSERT INTO EMP VALUES (7902, "FORD", "ANALYST", 7566,TO_DATE("3-DEC-1981", "DD-MON-YYYY"), 3000, NULL, 20);
1 row created.
SQL> INSERT INTO EMP VALUES (7934, "MILLER", "CLERK", 7782,TO_DATE("23-JAN-1982", "DD-MON-YYYY"), 1300, NULL, 10);
1 row created.
SQL>
SQL> CREATE TABLE DEPT (DEPTNO NUMBER(2),DNAME VARCHAR2(14),LOC VARCHAR2(13) );
Table created.
SQL>
SQL> INSERT INTO DEPT VALUES (10, "ACCOUNTING", "NEW YORK");
1 row created.
SQL> INSERT INTO DEPT VALUES (20, "RESEARCH", "DALLAS");
1 row created.
SQL> INSERT INTO DEPT VALUES (30, "SALES", "CHICAGO");
1 row created.
SQL> INSERT INTO DEPT VALUES (40, "OPERATIONS", "BOSTON");
1 row created.
SQL>
SQL> select * from emp;
     EMPNO ENAME      JOB              MGR HIREDATE         SAL       COMM     DEPTNO
---------- ---------- --------- ---------- --------- ---------- ---------- ----------
      7369 SMITH      CLERK           7902 17-DEC-80        800                    20
      7499 ALLEN      SALESMAN        7698 20-FEB-81       1600        300         30
      7521 WARD       SALESMAN        7698 22-FEB-81       1250        500         30
      7566 JONES      MANAGER         7839 02-APR-81       2975                    20
      7654 MARTIN     SALESMAN        7698 28-SEP-81       1250       1400         30
      7698 BLAKE      MANAGER         7839 01-MAY-81       2850                    30
      7782 CLARK      MANAGER         7839 09-JUN-81       2450                    10
      7788 SCOTT      ANALYST         7566 09-DEC-82       3000                    20
      7839 KING       PRESIDENT            17-NOV-81       5000                    10
      7844 TURNER     SALESMAN        7698 08-SEP-81       1500          0         30
      7876 ADAMS      CLERK           7788 12-JAN-83       1100                    20
      7900 JAMES      CLERK           7698 03-DEC-81        950                    30
      7902 FORD       ANALYST         7566 03-DEC-81       3000                    20
      7934 MILLER     CLERK           7782 23-JAN-82       1300                    10
14 rows selected.
SQL> select * from dept;
    DEPTNO DNAME          LOC
---------- -------------- -------------
        10 ACCOUNTING     NEW YORK
        20 RESEARCH       DALLAS
        30 SALES          CHICAGO
        40 OPERATIONS     BOSTON
SQL>
SQL> SELECT a.dname, b.empno, b.ename
  2      FROM dept a, emp b
  3      WHERE a.deptno=b.deptno(+)
  4      ORDER BY deptno;
    ORDER BY deptno
             *
ERROR at line 4:
ORA-00918: column ambiguously defined

SQL>
SQL>
SQL> drop table emp;
Table dropped.
SQL> drop table dept;
Table dropped.


Left and Right Outer Joins

Outer joins can be split into two types:

  1. Left outer joins
  2. Right outer joins

To understand the difference between left and right outer joins, consider the following syntax:



SELECT ...
FROM table1, table2
...


Assume the tables are to be joined on table1.column1 and table2.column2.

Assume table1 contains a row with a null value in column1.

To perform a left outer join, the WHERE clause is

WHERE table1.column1 = table2.column2 (+);

In a left outer join, the outer join operator is actually on the right of the equality operator.

Next, assume table2 contains a row with a null value in column2.

To perform a right outer join, you switch the position of the outer join operator to the left of the equality operator and the WHERE clause becomes WHERE table1.column1 (+) = table2.column2;

Depending on whether table1 and table2 both contain rows with null values, you get different results depending on whether you use a left or right outer join.

Quote from:

Oracle Database 10g SQL (Osborne ORACLE Press Series) (Paperback)

# Paperback: 608 pages

# Publisher: McGraw-Hill Osborne Media; 1st edition (February 20, 2004)

# Language: English

# ISBN-10: 0072229810

# ISBN-13: 978-0072229813

Left Outer Join

SQL>
SQL> CREATE TABLE Room (
  2     RoomID   INT NOT NULL PRIMARY KEY,
  3     Comments VARCHAR(50),
  4     Capacity INT);
Table created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (1,"Main hall",500);
1 row created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (2,"Science Department",200);
1 row created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (3,"Science Room 1",100);
1 row created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (4,"Languages Block",300);
1 row created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (5,"Languages Room 1",75);
1 row created.
SQL>
SQL>
SQL>
SQL> CREATE TABLE Class (
  2     ClassID     INT NOT NULL PRIMARY KEY,
  3     CourseID    INT NOT NULL,
  4     InstructorID INT NOT NULL,
  5     RoomID      INT NOT NULL,
  6     Time        VARCHAR(50));
Table created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (1,1,1,6,"Mon 09:00-11:00");
1 row created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (2,2,1,5,"Mon 11:00-12:00, Thu 09:00-11:00");
1 row created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (3,3,2,3,"Mon 14:00-16:00");
1 row created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (4,4,3,2,"Tue 10:00-12:00, Thu 14:00-15:00");
1 row created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (5,5,2,9,"Tue 14:00-16:00");
1 row created.
SQL>
SQL>
SQL>
SQL> SELECT Room.RoomID, Class.Time
  2  FROM Room
  3     LEFT OUTER JOIN Class
  4     ON Room.RoomID = Class.RoomID
  5  ORDER BY Room.RoomID;
    ROOMID TIME
---------- --------------------------------------------------
         1
         2 Tue 10:00-12:00, Thu 14:00-15:00
         3 Mon 14:00-16:00
         4
         5 Mon 11:00-12:00, Thu 09:00-11:00
5 rows selected.
SQL>
SQL>
SQL>
SQL> drop table Room;
Table dropped.
SQL> drop table Class;
Table dropped.


LEFT OUTER JOIN tableName ON joined columns

SQL>
SQL> CREATE TABLE emps (
  2    emp varchar(30)
  3   ,title    varchar(30)
  4  );
Table created.
SQL>
SQL> INSERT INTO emps VALUES ("Tom","Programmer");
1 row created.
SQL> INSERT INTO emps VALUES ("Jack","Tester");
1 row created.
SQL> INSERT INTO emps VALUES ("Mary","Technician");
1 row created.
SQL>
SQL> CREATE TABLE JobLevel (
  2    title     varchar(30)
  3   ,rank    varchar(30)
  4  );
Table created.
SQL>
SQL> INSERT INTO JobLevel VALUES ("Programmer","Level1");
1 row created.
SQL> INSERT INTO JobLevel VALUES ("Tester","Level2");
1 row created.
SQL> INSERT INTO JobLevel VALUES ("Technician","Level3");
1 row created.
SQL>
SQL> CREATE TABLE salary (
  2    rank     varchar(30)
  3   ,payment  DECIMAL(10,2)
  4  );
Table created.
SQL>
SQL> INSERT INTO salary VALUES ("Level1",2000.00);
1 row created.
SQL> INSERT INTO salary VALUES ("Level2",3000.00);
1 row created.
SQL> INSERT INTO salary VALUES ("Level3",5000.00);
1 row created.
SQL> INSERT INTO salary VALUES ("Level4",6000.00);
1 row created.
SQL>
SQL> select * from emps;

EMP
------------------------------
TITLE
------------------------------
Tom
Programmer
Jack
Tester
Mary
Technician

3 rows selected.
SQL> select * from JobLevel;

TITLE
------------------------------
RANK
------------------------------
Programmer
Level1
Tester
Level2
Technician
Level3
3 rows selected.
SQL> select * from salary;

RANK                               PAYMENT
------------------------------  ----------
Level1                                2000
Level2                                3000
Level3                                5000
Level4                                6000
4 rows selected.
SQL>
SQL>
SQL> SELECT salary.rank
  2  FROM salary LEFT OUTER JOIN JobLevel ON (salary.rank = JobLevel.rank)
  3  WHERE JobLevel.rank IS NULL;

RANK
------------------------------
Level4

1 row selected.
SQL>
SQL>
SQL> DROP TABLE emps;
Table dropped.
SQL> DROP TABLE JobLevel;
Table dropped.
SQL> DROP TABLE salary;
Table dropped.
SQL>
SQL>


LEFT OUTER JOIN vs RIGHT OUTER JOIN

SQL>
SQL> CREATE TABLE project (
  2    pro_id              NUMBER(4),
  3    pro_name            VARCHAR2(40),
  4    budget          NUMBER(9,2),
  5    CONSTRAINT project_pk   PRIMARY KEY (pro_id)
  6  );
Table created.
SQL>
SQL>
SQL> INSERT INTO project(pro_id, pro_name, budget)VALUES (1001, "A",12345);
1 row created.
SQL> INSERT INTO project(pro_id, pro_name, budget)VALUES (1002, "ERP",23456);
1 row created.
SQL> INSERT INTO project(pro_id, pro_name, budget)VALUES (1003, "SQL",34567);
1 row created.
SQL> INSERT INTO project(pro_id, pro_name, budget)VALUES (1004, "CRM",45678);
1 row created.
SQL> INSERT INTO project(pro_id, pro_name, budget)VALUES (1005, "VPN",56789);
1 row created.
SQL>
SQL>
SQL>
SQL> CREATE TABLE server_usage (
  2    pro_id                   NUMBER(4),
  3    emp_id                  NUMBER,
  4    time_log_date                DATE,
  5    hours_logged                 NUMBER(8,2),
  6    dollars_charged              NUMBER(8,2),
  7    CONSTRAINT server_usage_pk  PRIMARY KEY (pro_id, emp_id, time_log_date)
  8  );
Table created.
SQL> INSERT INTO server_usage(pro_id, emp_id, time_log_date, hours_logged, dollars_charged)
  2                    VALUES (1001,101,to_date("4-Apr-2004","dd-mon-yyyy"),1123,222);
1 row created.
SQL> INSERT INTO server_usage(pro_id, emp_id, time_log_date, hours_logged, dollars_charged)
  2                    VALUES (1002,102,to_date("4-Apr-2005","dd-mon-yyyy"),1124,223);
1 row created.
SQL> INSERT INTO server_usage(pro_id, emp_id, time_log_date, hours_logged, dollars_charged)
  2                    VALUES (1003,103,to_date("4-Apr-2006","dd-mon-yyyy"),1125,224);
1 row created.
SQL> INSERT INTO server_usage(pro_id, emp_id, time_log_date, hours_logged, dollars_charged)
  2                    VALUES (1004,104,to_date("4-Apr-2007","dd-mon-yyyy"),1126,225);
1 row created.
SQL> INSERT INTO server_usage(pro_id, emp_id, time_log_date, hours_logged, dollars_charged)
  2                    VALUES (1005,105,to_date("4-Apr-2008","dd-mon-yyyy"),1127,226);
1 row created.
SQL> INSERT INTO server_usage(pro_id, emp_id, time_log_date, hours_logged, dollars_charged)
  2                    VALUES (1001,106,to_date("4-Apr-2009","dd-mon-yyyy"),1128,227);
1 row created.
SQL> INSERT INTO server_usage(pro_id, emp_id, time_log_date, hours_logged, dollars_charged)
  2                    VALUES (1002,107,to_date("4-Apr-2010","dd-mon-yyyy"),1129,228);
1 row created.
SQL>
SQL>
SQL> SET ECHO ON
SQL> SELECT p.pro_name,  ph.time_log_date, ph.hours_logged
  2  FROM project p LEFT OUTER JOIN server_usage ph
  3       ON p.pro_id = ph.pro_id;
A
04-APR-04         1123
ERP
04-APR-05         1124
SQL
04-APR-06         1125
CRM
04-APR-07         1126
VPN
04-APR-08         1127
A
04-APR-09         1128
ERP
04-APR-10         1129

7 rows selected.
SQL>
SQL> SELECT p.pro_name,  ph.time_log_date, ph.hours_logged
  2  FROM server_usage ph RIGHT OUTER JOIN project p
  3       ON p.pro_id = ph.pro_id;
A
04-APR-04         1123
ERP
04-APR-05         1124
SQL
04-APR-06         1125
CRM
04-APR-07         1126
VPN
04-APR-08         1127
A
04-APR-09         1128
ERP
04-APR-10         1129

7 rows selected.
SQL>
SQL> drop table server_usage;
Table dropped.
SQL> drop table project;
Table dropped.


Perform outer joins in combination with self joins, employee and job tables

SQL>
SQL>
SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    EMPNO         NUMBER(3),
  3    ENAME         VARCHAR2(15 BYTE),
  4    HIREDATE      DATE,
  5    ORIG_SALARY   NUMBER(6),
  6    CURR_SALARY   NUMBER(6),
  7    REGION        VARCHAR2(1 BYTE),
  8    MANAGER_ID    NUMBER(3)
  9  )
 10  /
Table created.
SQL>
SQL> create table job (
  2    EMPNO         NUMBER(3),
  3    jobtitle      VARCHAR2(20 BYTE)
  4  )
  5  /
Table created.
SQL>
SQL> insert into job (EMPNO, Jobtitle) values (1,"Tester");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (2,"Accountant");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (3,"Developer");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (4,"COder");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (5,"Director");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (6,"Mediator");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (7,"Proffessor");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (8,"Programmer");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (9,"Developer");
1 row created.
SQL>
SQL>
SQL> -- prepare data
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION, MANAGER_ID)
  2               values (1,      "Jason", to_date("19960725","YYYYMMDD"), 1234,              8767,         "E",    2)
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION, MANAGER_ID)
  2               values (2,      "John",  to_date("19970715","YYYYMMDD"), 2341,              3456,         "W",    3)
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION, MANAGER_ID)
  2               values (3,      "Joe",   to_date("19860125","YYYYMMDD"), 4321,              5654,         "E",    3)
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION, MANAGER_ID)
  2               values (4,      "Tom",   to_date("20060913","YYYYMMDD"), 2413,              6787,         "W",    4)
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION, MANAGER_ID)
  2               values (5,      "Jane",  to_date("20050417","YYYYMMDD"), 7654,              4345,         "E",    4)
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION, MANAGER_ID)
  2               values (6,      "James", to_date("20040718","YYYYMMDD"), 5679,              6546,         "W",    5)
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION, MANAGER_ID)
  2               values (7,      "Jodd",  to_date("20030720","YYYYMMDD"), 5438,              7658,         "E",    6)
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (8,      "Joke",  to_date("20020101","YYYYMMDD"), 8765,              4543,         "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (9,      "Jack",  to_date("20010829","YYYYMMDD"), 7896,              1232,         "E")
  3  /
1 row created.
SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /
     EMPNO ENAME           HIREDATE  ORIG_SALARY CURR_SALARY R MANAGER_ID
---------- --------------- --------- ----------- ----------- - ----------
         1 Jason           25-JUL-96        1234        8767 E          2
         2 John            15-JUL-97        2341        3456 W          3
         3 Joe             25-JAN-86        4321        5654 E          3
         4 Tom             13-SEP-06        2413        6787 W          4
         5 Jane            17-APR-05        7654        4345 E          4
         6 James           18-JUL-04        5679        6546 W          5
         7 Jodd            20-JUL-03        5438        7658 E          6
         8 Joke            01-JAN-02        8765        4543 W
         9 Jack            29-AUG-01        7896        1232 E
9 rows selected.
SQL> select * from job
  2  /
     EMPNO JOBTITLE
---------- --------------------
         1 Tester
         2 Accountant
         3 Developer
         4 COder
         5 Director
         6 Mediator
         7 Proffessor
         8 Programmer
         9 Developer
9 rows selected.
SQL>
SQL>
SQL> SELECT w.ename || " works for " ||
  2   NVL(m.ename, "the shareholders")
  3  FROM employee w, employee m
  4  WHERE w.manager_id = m.empno;
W.ENAME||"WORKSFOR"||NVL(M.ENAME,"THESHARE
------------------------------------------
Jason works for John
Joe works for Joe
John works for Joe
Jane works for Tom
Tom works for Tom
James works for Jane
Jodd works for James
7 rows selected.
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL> drop table job
  2  /
Table dropped.
SQL>


Right join with where in clause

SQL>
SQL>
SQL> CREATE TABLE emp
  2  (
  3     cid                NUMBER,
  4     lname         VARCHAR2(40) ,
  5     city              VARCHAR2(30) ,
  6     customer_state             VARCHAR2(40),
  7     country_id                 CHAR(2) ,
  8     customer_credit            NUMBER
  9  );
Table created.
SQL>
SQL> CREATE TABLE sales(
  2    product_id                NUMBER(6),
  3    cid               NUMBER,
  4    time_id                   DATE,
  5    channel_id                CHAR(1),
  6    promo_id                  NUMBER(6),
  7    sold             NUMBER(3),
  8    amount                    NUMBER(10,2),
  9    cost                      NUMBER(10,2)
 10  );
Table created.
SQL>
SQL>
SQL>
SQL> select c.cid, c.lname, s.product_id, s.sold
  2  from sales s right join emp c
  3     on c.cid = s.cid
  4  where c.cid in (1,80);
no rows selected
SQL>
SQL> drop table sales;
Table dropped.
SQL> drop table emp;
Table dropped.
SQL>
SQL>


Right Outer Join

SQL>
SQL>
SQL> CREATE TABLE Room (
  2     RoomID   INT NOT NULL PRIMARY KEY,
  3     Comments VARCHAR(50),
  4     Capacity INT);
Table created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (1,"Main hall",500);
1 row created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (2,"Science Department",200);
1 row created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (3,"Science Room 1",100);
1 row created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (4,"Languages Block",300);
1 row created.
SQL>
SQL>
SQL>
SQL> CREATE TABLE Class (
  2     ClassID     INT NOT NULL PRIMARY KEY,
  3     CourseID    INT NOT NULL,
  4     InstructorID INT NOT NULL,
  5     RoomID      INT NOT NULL,
  6     Time        VARCHAR(50));
Table created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (1,1,1,6,"Mon 09:00-11:00");
1 row created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (2,2,1,5,"Mon 11:00-12:00, Thu 09:00-11:00");
1 row created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (3,3,2,3,"Mon 14:00-16:00");
1 row created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (4,4,3,2,"Tue 10:00-12:00, Thu 14:00-15:00");
1 row created.
SQL>
SQL>
SQL>
SQL> SELECT Room.RoomID, Class.Time
  2  FROM Room
  3     RIGHT OUTER JOIN Class
  4     ON Room.RoomID = Class.RoomID
  5  ORDER BY Room.RoomID;
    ROOMID TIME
---------- --------------------------------------------------
         2 Tue 10:00-12:00, Thu 14:00-15:00
         3 Mon 14:00-16:00
           Mon 09:00-11:00
           Mon 11:00-12:00, Thu 09:00-11:00
4 rows selected.
SQL>
SQL> drop table Room;
Table dropped.
SQL> drop table Class;
Table dropped.


Right Outer Join(room vs class)

SQL>
SQL>
SQL> CREATE TABLE Room (
  2     RoomID   INT NOT NULL PRIMARY KEY,
  3     Comments VARCHAR(50),
  4     Capacity INT);
Table created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (1,"Main hall",500);
1 row created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (2,"Science Department",200);
1 row created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (3,"Science Room 1",100);
1 row created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (4,"Languages Block",300);
1 row created.
SQL> INSERT INTO Room (RoomID,Comments,Capacity) VALUES (5,"Languages Room 1",75);
1 row created.
SQL>
SQL>
SQL>
SQL> CREATE TABLE Class (
  2     ClassID     INT NOT NULL PRIMARY KEY,
  3     CourseID    INT NOT NULL,
  4     InstructorID INT NOT NULL,
  5     RoomID      INT NOT NULL,
  6     Time        VARCHAR(50));
Table created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (1,1,1,6,"Mon 09:00-11:00");
1 row created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (2,2,1,5,"Mon 11:00-12:00, Thu 09:00-11:00");
1 row created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (3,3,2,3,"Mon 14:00-16:00");
1 row created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (4,4,3,2,"Tue 10:00-12:00, Thu 14:00-15:00");
1 row created.
SQL> INSERT INTO Class (ClassID,CourseID,InstructorID,RoomID,Time) VALUES (5,5,2,9,"Tue 14:00-16:00");
1 row created.
SQL>
SQL>
SQL>
SQL> SELECT Room.RoomID, Class.Time
  2  FROM Class
  3     RIGHT OUTER JOIN Room
  4     ON Class.RoomID = Room.RoomID
  5  ORDER BY Room.RoomID;
    ROOMID TIME
---------- --------------------------------------------------
         1
         2 Tue 10:00-12:00, Thu 14:00-15:00
         3 Mon 14:00-16:00
         4
         5 Mon 11:00-12:00, Thu 09:00-11:00
5 rows selected.
SQL>
SQL> drop table Room;
Table dropped.
SQL> drop table Class;
Table dropped.


Right outer join with group by

SQL>
SQL>
SQL> create table employees(
  2    empno      NUMBER(4)
  3  , ename      VARCHAR2(8)
  4  , init       VARCHAR2(5)
  5  , job        VARCHAR2(8)
  6  , mgr        NUMBER(4)
  7  , bdate      DATE
  8  , msal       NUMBER(6,2)
  9  , comm       NUMBER(6,2)
 10  , deptno     NUMBER(2) ) ;
Table created.
SQL>
SQL>
SQL> insert into employees values(1,"Jason",  "N",  "TRAINER", 2,   date "1965-12-18",  800 , NULL,  10);
1 row created.
SQL> insert into employees values(2,"Jerry",  "J",  "SALESREP",3,   date "1966-11-19",  1600, 300,   10);
1 row created.
SQL> insert into employees values(3,"Jord",   "T" , "SALESREP",4,   date "1967-10-21",  1700, 500,   20);
1 row created.
SQL> insert into employees values(4,"Mary",   "J",  "MANAGER", 5,   date "1968-09-22",  1800, NULL,  20);
1 row created.
SQL> insert into employees values(5,"Joe",    "P",  "SALESREP",6,   date "1969-08-23",  1900, 1400,  30);
1 row created.
SQL> insert into employees values(6,"Black",  "R",  "MANAGER", 7,   date "1970-07-24",  2000, NULL,  30);
1 row created.
SQL> insert into employees values(7,"Red",    "A",  "MANAGER", 8,   date "1971-06-25",  2100, NULL,  40);
1 row created.
SQL> insert into employees values(8,"White",  "S",  "TRAINER", 9,   date "1972-05-26",  2200, NULL,  40);
1 row created.
SQL> insert into employees values(9,"Yellow", "C",  "DIRECTOR",10,  date "1973-04-27",  2300, NULL,  20);
1 row created.
SQL> insert into employees values(10,"Pink",  "J",  "SALESREP",null,date "1974-03-28",  2400, 0,     30);
1 row created.
SQL>
SQL>
SQL> create table departments
  2  ( deptno NUMBER(2)
  3  , dname  VARCHAR2(10)
  4  , location VARCHAR2(20)
  5  , mgr    NUMBER(4)
  6  ) ;
Table created.
SQL>
SQL> insert into departments values (10,"ACCOUNTING","NEW YORK" ,  2);
1 row created.
SQL> insert into departments values (20,"TRAINING",  "VANCOUVER",  3);
1 row created.
SQL> insert into departments values (30,"SALES",     "CHICAGO",    4);
1 row created.
SQL> insert into departments values (40,"HR",        "BOSTON",     5);
1 row created.
SQL>
SQL>
SQL> select deptno, count(*)
  2  from   employees e
  3         right outer join
  4         departments d
  5         using (deptno)
  6  group  by deptno;
    DEPTNO   COUNT(*)
---------- ----------
        30          3
        20          3
        40          2
        10          2
SQL>
SQL> drop table employees;
Table dropped.
SQL>
SQL> drop table departments;
Table dropped.
SQL>
SQL>


Right outer join with using statement

SQL>
SQL>
SQL> create table employees(
  2    empno      NUMBER(4)
  3  , ename      VARCHAR2(8)
  4  , init       VARCHAR2(5)
  5  , job        VARCHAR2(8)
  6  , mgr        NUMBER(4)
  7  , bdate      DATE
  8  , msal       NUMBER(6,2)
  9  , comm       NUMBER(6,2)
 10  , deptno     NUMBER(2) ) ;
Table created.
SQL>
SQL>
SQL> insert into employees values(1,"Jason",  "N",  "TRAINER", 2,   date "1965-12-18",  800 , NULL,  10);
1 row created.
SQL> insert into employees values(2,"Jerry",  "J",  "SALESREP",3,   date "1966-11-19",  1600, 300,   10);
1 row created.
SQL> insert into employees values(3,"Jord",   "T" , "SALESREP",4,   date "1967-10-21",  1700, 500,   20);
1 row created.
SQL> insert into employees values(4,"Mary",   "J",  "MANAGER", 5,   date "1968-09-22",  1800, NULL,  20);
1 row created.
SQL> insert into employees values(5,"Joe",    "P",  "SALESREP",6,   date "1969-08-23",  1900, 1400,  30);
1 row created.
SQL> insert into employees values(6,"Black",  "R",  "MANAGER", 7,   date "1970-07-24",  2000, NULL,  30);
1 row created.
SQL> insert into employees values(7,"Red",    "A",  "MANAGER", 8,   date "1971-06-25",  2100, NULL,  40);
1 row created.
SQL> insert into employees values(8,"White",  "S",  "TRAINER", 9,   date "1972-05-26",  2200, NULL,  40);
1 row created.
SQL> insert into employees values(9,"Yellow", "C",  "DIRECTOR",10,  date "1973-04-27",  2300, NULL,  20);
1 row created.
SQL> insert into employees values(10,"Pink",  "J",  "SALESREP",null,date "1974-03-28",  2400, 0,     30);
1 row created.
SQL>
SQL>
SQL> create table departments
  2  ( deptno NUMBER(2)
  3  , dname  VARCHAR2(10)
  4  , location VARCHAR2(20)
  5  , mgr    NUMBER(4)
  6  ) ;
Table created.
SQL>
SQL> insert into departments values (10,"ACCOUNTING","NEW YORK" ,  2);
1 row created.
SQL> insert into departments values (20,"TRAINING",  "VANCOUVER",  3);
1 row created.
SQL> insert into departments values (30,"SALES",     "CHICAGO",    4);
1 row created.
SQL> insert into departments values (40,"HR",        "BOSTON",     5);
1 row created.
SQL>
SQL>
SQL> select deptno, d.location
  2  ,      e.ename, e.init
  3  from   employees e
  4         right outer join
  5         departments d
  6         using (deptno)
  7  order  by deptno, e.ename;
    DEPTNO LOCATION             ENAME    INIT
---------- -------------------- -------- -----
        10 NEW YORK             Jason    N
        10 NEW YORK             Jerry    J
        20 VANCOUVER            Jord     T
        20 VANCOUVER            Mary     J
        20 VANCOUVER            Yellow   C
        30 CHICAGO              Black    R
        30 CHICAGO              Joe      P
        30 CHICAGO              Pink     J
        40 BOSTON               Red      A
        40 BOSTON               White    S
10 rows selected.
SQL>
SQL> drop table employees;
Table dropped.
SQL>
SQL> drop table departments;
Table dropped.
SQL>


Understanding Outer Joins

  1. An outer join retrieves a row even when one of the columns in the join contains a null value.
  2. You perform an outer join by supplying the outer join operator in the join condition.
  3. The outer join operator is a plus character in parentheses (+).
  4. The outer join operator (+) is on the column that contains the null value.



SQL> -- create demo table
SQL> create table Employee(
  2    EMPNO         NUMBER(3),
  3    ENAME         VARCHAR2(15 BYTE),
  4    HIREDATE      DATE,
  5    ORIG_SALARY   NUMBER(6),
  6    CURR_SALARY   NUMBER(6),
  7    REGION        VARCHAR2(1 BYTE)
  8  )
  9  /
Table created.
SQL>
SQL> create table job (
  2    EMPNO         NUMBER(3),
  3    jobtitle      VARCHAR2(20 BYTE)
  4  )
  5  /
Table created.
SQL>
SQL> insert into job (EMPNO, Jobtitle) values (1,"Tester");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (2,"Accountant");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (3,"Developer");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (4,"COder");
1 row created.
SQL> insert into job (EMPNO, Jobtitle) values (5,"Director");
1 row created.
SQL>
SQL> insert into job (EMPNO, Jobtitle) values (9,"Developer");
1 row created.
SQL>
SQL>
SQL> -- prepare data
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (1,      "Jason", to_date("19960725","YYYYMMDD"), 1234,              8767,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (2,      "John",  to_date("19970715","YYYYMMDD"), 2341,              3456,         "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (3,      "Joe",   to_date("19860125","YYYYMMDD"), 4321,              5654,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (4,      "Tom",   to_date("20060913","YYYYMMDD"), 2413,              6787,         "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (5,      "Jane",  to_date("20050417","YYYYMMDD"), 7654,              4345,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (6,      "James", to_date("20040718","YYYYMMDD"), 5679,              6546,         "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (7,      "Jodd",  to_date("20030720","YYYYMMDD"), 5438,              7658,         "E")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (8,      "Joke",  to_date("20020101","YYYYMMDD"), 8765,              4543,         "W")
  3  /
1 row created.
SQL> insert into Employee(EMPNO,  EName,   HIREDATE,                       ORIG_SALARY,       CURR_SALARY,  REGION)
  2               values (9,      "Jack",  to_date("20010829","YYYYMMDD"), 7896,              1232,         "E")
  3  /
1 row created.
SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /
     EMPNO ENAME           HIREDATE  ORIG_SALARY CURR_SALARY R
---------- --------------- --------- ----------- ----------- -
         1 Jason           25-JUL-96        1234        8767 E
         2 John            15-JUL-97        2341        3456 W
         3 Joe             25-JAN-86        4321        5654 E
         4 Tom             13-SEP-06        2413        6787 W
         5 Jane            17-APR-05        7654        4345 E
         6 James           18-JUL-04        5679        6546 W
         7 Jodd            20-JUL-03        5438        7658 E
         8 Joke            01-JAN-02        8765        4543 W
         9 Jack            29-AUG-01        7896        1232 E
9 rows selected.
SQL> select * from job
  2  /
     EMPNO JOBTITLE
---------- --------------------
         1 Tester
         2 Accountant
         3 Developer
         4 COder
         5 Director
         9 Developer
6 rows selected.
SQL>
SQL>
SQL> SELECT e.ename, j.jobtitle FROM employee e, job j WHERE e.empno = j.empno (+);
ENAME           JOBTITLE
--------------- --------------------
Jason           Tester
John            Accountant
Joe             Developer
Tom             COder
Jane            Director
Jack            Developer
Joke
James
Jodd
9 rows selected.
SQL>
SQL> SELECT e.ename, j.jobtitle FROM employee e, job j WHERE e.empno (+) = j.empno;
ENAME           JOBTITLE
--------------- --------------------
Jason           Tester
John            Accountant
Joe             Developer
Tom             COder
Jane            Director
Jack            Developer
6 rows selected.
SQL>
SQL> SELECT e.ename, j.jobtitle FROM employee e, job j WHERE j.empno (+) = e.empno;
ENAME           JOBTITLE
--------------- --------------------
Jason           Tester
John            Accountant
Joe             Developer
Tom             COder
Jane            Director
Jack            Developer
Joke
James
Jodd
9 rows selected.
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL> drop table job
  2  /
Table dropped.
SQL>