Oracle: minus | in | exists

解释及例子:
MINUS Query:
http://www.techonthenet.com/sql/minus.php

IN Function:
http://www.techonthenet.com/sql/in.php

EXISTS Condition:
http://www.techonthenet.com/sql/exists.php


实例代码:
引用
SQL> select distinct deptno from dept

    DEPTNO
----------
        10
        20
        30
        40

4 rows selected.
SQL> select distinct deptno from emp

    DEPTNO
----------
        30
        20
        10

3 rows selected.
SQL> select distinct  deptno from dept  
where deptno in  
(select distinct deptno from emp)

    DEPTNO
----------
        30
        20
        10

3 rows selected.
SQL> select distinct deptno from dept  
where exists  
(select distinct deptno from emp where dept.deptno = emp.deptno)

    DEPTNO
----------
        30
        20
        10

3 rows selected.
SQL> select distinct deptno from dept  
minus  
select distinct deptno from emp

    DEPTNO
----------
        40

1 row selected.
SQL> select distinct  deptno from dept
where deptno not in  
(select distinct deptno from emp)

    DEPTNO
----------
        40

1 row selected.
SQL> select distinct deptno from dept  
where not exists  
(select distinct deptno from emp where dept.deptno = emp.deptno)

    DEPTNO
----------
        40

1 row selected.

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转载自wuaner.iteye.com/blog/1671927