miércoles, 23 de noviembre de 2011

JOINS

Example of a Left Outer Join 1

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.



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.