【OCP-12c】CUUG 071题库考试原题及答案解析（13）

13、（6-7） choose two
Which two statements are true regarding operators used with subqueries? (Choose two.)
A) =ANY and =ALL operators have the same functionality.
E) The NOT IN operator is equivalent to is NULL.
C) The D) The NOT operator can be used with IN, ANY and ALL operators.
E) The IN operator cannot be used in single-row subqueries.
Answer：CD
（解析：051 曾经出现过，但是当时是单选题，答案是 D，这个语法比较少见。
其实就是把 NOT 放到整个表达式之前，下面条件执行的结果都是一样，考大家的逻辑思维能力：
WHERE NOT col IN (SELECT ...)（也可以是 WHERE col not IN (SELECT ...)）
WHERE NOT col = ANY (SELECT ...)（大于、小于都可以）
WHERE NOT col = ALL (SELECT ...)（大于、小于都可以）
SQL> select deptno from emp
2 where not deptno in (select deptno from dept where deptno=10);
DEPTNO
----------
20
30
30
....
或者：
select deptno from emp
where not deptno = all (select deptno from dept where deptno=10);