ALL比较符的用法
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Compares a value to each value in a list or returned by a query. Must be preceded by =, !=, >, <, <=, >=. Can be followed by any expression or subquery that returns one or more values. Evaluates to |
SELECT * FROM employees
WHERE salary = ANY
(SELECT salary
FROM employees
WHERE department_id = 30)
ORDER BY employee_id;
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Compares a value to every value in a list or returned by a query. Must be preceded by =, !=, >, <, <=, >=. Can be followed by any expression or subquery that returns one or more values. Evaluates to |
SELECT * FROM employees
WHERE salary >=
ALL (1400, 3000)
ORDER BY employee_id;
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官方参考： http://docs.oracle.com/cd/E11882_01/server.112/e41084/conditions002.htm#sthref1908
以scott/tiger 的emp表作为示例：
scott@TEST0924> 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 19-APR-87 3000 20
7839 KING PRESIDENT 17-NOV-81 5000 10
7844 TURNER SALESMAN 7698 08-SEP-81 1500 0 30
7876 ADAMS CLERK 7788 23-MAY-87 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.
ALL:类似AND操作符，即要满足所有条件，大于所有值，即大于最大值。
scott@TEST0924> select empno,sal from emp
2 where sal>all(2000,3000);
EMPNO SAL
---------- ----------
7839 5000
等价于大于所有的值
scott@TEST0924> select empno,sal from emp
2 where sal>2000 and sal>3000;
EMPNO SAL
---------- ----------
7839 5000
等价于大于最大的那个值
scott@TEST0924> select empno,sal from emp
2 where sal>3000;
EMPNO SAL
---------- ----------
7839 5000
如果all后面跟着子查询：
scott@TEST0924> SELECT e2.sal FROM emp e2 WHERE e2.deptno = 20;
SAL
----------
800
2975
3000
1100
3000
scott@TEST0924> SELECT e1.empno, e1.sal
2 FROM emp e1
3 WHERE e1.sal > ALL (SELECT e2.sal
4 FROM emp e2
5 WHERE e2.deptno = 20);
EMPNO SAL
---------- ----------
7839 5000
等价于
scott@TEST0924> SELECT e1.empno, e1.sal
2 FROM emp e1
3 WHERE e1.sal > ALL (800,2975,3000,1100,3000);
EMPNO SAL
---------- ----------
7839 5000
等价于大于最大值：
scott@TEST0924> SELECT e1.empno, e1.sal FROM emp e1
2 WHERE e1.sal > 3000;
EMPNO SAL
---------- ----------
7839 5000
等价于
scott@TEST0924> SELECT e1.empno, e1.sal
2 FROM emp e1
3 WHERE NOT (e1.sal <= ANY (SELECT e2.sal
4 FROM emp e2
5 WHERE e2.deptno = 20));
EMPNO SAL
---------- ----------
7839 5000
也等价于
scott@TEST0924> SELECT e1.empno, e1.sal
2 FROM emp e1
3 WHERE NOT EXISTS (SELECT e2.sal
4 FROM emp e2
5 WHERE e2.deptno = 20
6 AND e1.sal <= e2.sal);
EMPNO SAL
---------- ----------
7839 5000
如果all的子查询有返回值，则
- "x = ALL (...)": The value must match all the values in the list to evaluate to TRUE.所有值都要匹配
- "x != ALL (...)": The value must not match any values in the list to evaluate to TRUE.至少有一个值不匹配
- "x > ALL (...)": The value must be greater than the biggest value in the list to evaluate to TRUE.大于最大的值
- "x < ALL (...)": The value must be smaller than the smallest value in the list to evaluate to TRUE.小于最小的值
- "x >= ALL (...)": The value must be greater than or equal to the biggest value in the list to evaluate to TRUE.大于等于最大的值
- "x <= ALL (...)": The value must be smaller than or equal to the smallest value in the list to evaluate to TRUE.小于等于最小的值
如果all的子查询返回值为0行，则
scott@TEST0924> SELECT e2.sal FROM emp e2 WHERE e2.deptno = 100
2 ;
no rows selected
=ALL，按照原来的值输出
scott@TEST0924> SELECT e1.empno, e1.sal
2 FROM emp e1
3 WHERE e1.sal=ALL (SELECT e2.sal FROM emp e2 WHERE e2.deptno = 100);
EMPNO SAL
---------- ----------
7369 800
7499 1600
7521 1250
7566 2975
7654 1250
7698 2850
7782 2450
7788 3000
7839 5000
7844 1500
7876 1100
7900 950
7902 3000
7934 1300
14 rows selected.
!=ALL也按照原来的值输出，但不知道按什么排序的？
scott@TEST0924> SELECT e1.empno, e1.sal FROM emp e1
2 WHERE e1.sal!=ALL (SELECT e2.sal FROM emp e2 WHERE e2.deptno = 100);
EMPNO SAL
---------- ----------
7369 800
7902 3000
7788 3000
7698 2850
7782 2450
7839 5000
7654 1250
7521 1250
7499 1600
7876 1100
7900 950
7566 2975
7934 1300
7844 1500
14 rows selected.
<ALL,按原来的值降序输出
scott@TEST0924> SELECT e1.empno, e1.sal
2 FROM emp e1
3 WHERE e1.sal<ALL (SELECT e2.sal FROM emp e2 WHERE e2.deptno = 100);
EMPNO SAL
---------- ----------
7839 5000
7902 3000
7788 3000
7566 2975
7698 2850
7782 2450
7499 1600
7844 1500
7934 1300
7521 1250
7654 1250
7876 1100
7900 950
7369 800
14 rows selected.
<=ALL和<ALL一样按原来的值降序输出
scott@TEST0924> SELECT e1.empno, e1.sal
2 FROM emp e1
3 WHERE e1.sal<=ALL (SELECT e2.sal FROM emp e2 WHERE e2.deptno = 100);
EMPNO SAL
---------- ----------
7839 5000
7902 3000
7788 3000
7566 2975
7698 2850
7782 2450
7499 1600
7844 1500
7934 1300
7521 1250
7654 1250
7876 1100
7900 950
7369 800
14 rows selected.
>ALL和>=ALL,按原来的升序输出
scott@TEST0924> SELECT e1.empno, e1.sal
2 FROM emp e1
3 WHERE e1.sal > ALL (SELECT e2.sal FROM emp e2 WHERE e2.deptno = 100);
EMPNO SAL
---------- ----------
7369 800
7900 950
7876 1100
7521 1250
7654 1250
7934 1300
7844 1500
7499 1600
7782 2450
7698 2850
7566 2975
7788 3000
7902 3000
7839 5000
14 rows selected.
ANY比较符参考： http://blog.csdn.net/rlhua/article/details/12007309