查询练习：NOT INANYALLUNION

Posted 2021-03-01 direwolf22

1.NOT IN：

mysql> select * from teacher;
+---------+-------------+---------+---------------------+----------+------------+
| tea_num | tea_name    | tea_sex | tea_birth           | tea_prof | department |
+---------+-------------+---------+---------------------+----------+------------+
| 0435    | LiMei       | F       | 1983-02-24 00:00:00 | prof     | Computer   |
| 0436    | MaDi        | F       | 1984-01-23 00:00:00 | assist   | Bio        |
| 0437    | LiZhe       | F       | 1974-01-23 00:00:00 | prof     | Econ       |
| 0438    | ShaoGuoYing | F       | 1985-06-17 00:00:00 | prof     | Math       |
| 0439    | Susan       | F       | 1985-07-18 00:00:00 | assist   | Math       |
| 0440    | Mary        | F       | 1990-05-02 00:00:00 | lecturer | Econ       |
+---------+-------------+---------+---------------------+----------+------------+

查询Math与Econ不同职称的教师的tea_name与tea_prof：

Econ中的职称类型：

mysql> select tea_prof from teacher where department in (‘Econ‘);
+----------+
| tea_prof |
+----------+
| prof     |
| lecturer |
+----------+

Math中与它不同的：

mysql> select tea_name,tea_prof from teacher where department = ‘Math‘ and tea_prof not in (select tea_prof from teacher where department in (‘Econ‘));
+----------+----------+
| tea_name | tea_prof |
+----------+----------+
| Susan    | assist   |
+----------+----------+

同理：

mysql> select tea_name,tea_prof from teacher where department = ‘Econ‘ and tea_prof not in (select tea_prof from teacher where department in (‘Math‘));
+----------+----------+
| tea_name | tea_prof |
+----------+----------+
| Mary     | lecturer |
+----------+----------+

2条结果合在一起：union求并集

mysql> select tea_name,tea_prof from teacher where department = ‘Econ‘ and tea_prof not in (select tea_prof from teacher where department in (‘Math‘))
    -> union
    -> select tea_name,tea_prof from teacher where department = ‘Math‘ and tea_prof not in (select tea_prof from teacher where department in (‘Econ‘));
+----------+----------+
| tea_name | tea_prof |
+----------+----------+
| Mary     | lecturer |
| Susan    | assist   |
+----------+----------+

 3.查询课程号为2-271和1-245的成绩：

mysql> select * from score where cour_num in (‘2-271‘);
+---------+----------+--------+
| stu_num | cour_num | degree |
+---------+----------+--------+
| 11423   | 2-271    |     75 |
| 11425   | 2-271    |     89 |
| 11426   | 2-271    |     82 |
+---------+----------+--------+

mysql> select * from score where cour_num in (‘1-245‘);
+---------+----------+--------+
| stu_num | cour_num | degree |
+---------+----------+--------+
| 11423   | 1-245    |     84 |
| 11426   | 1-245    |     61 |
| 11427   | 1-245    |     78 |
+---------+----------+--------+

any:任意一个

mysql> select * from score where cour_num=‘2-271‘
    -> and degree>any(select degree from score where cour_num=‘1-245‘);
+---------+----------+--------+
| stu_num | cour_num | degree |
+---------+----------+--------+
| 11423   | 2-271    |     75 |
| 11425   | 2-271    |     89 |
| 11426   | 2-271    |     82 |
+---------+----------+--------+

按成绩降序排列：

mysql> select * from score where cour_num=‘2-271‘
    -> and degree>any(select degree from score where cour_num=‘1-245‘)
    -> order by degree desc;
+---------+----------+--------+
| stu_num | cour_num | degree |
+---------+----------+--------+
| 11425   | 2-271    |     89 |
| 11426   | 2-271    |     82 |
| 11423   | 2-271    |     75 |
+---------+----------+--------+

4.all:所有

mysql> select * from score
    -> where cour_num=‘2-271‘
    -> and degree>all(select degree from score where cour_num=‘1-245‘);
+---------+----------+--------+
| stu_num | cour_num | degree |
+---------+----------+--------+
| 11425   | 2-271    |     89 |
+---------+----------+--------+