database homework1

mysql> select * from teacher_info;
+----+------+-----+--------+---------+
| id | name | age | salary | job     |
+----+------+-----+--------+---------+
|  1 | nick |  18 |  30000 | teacher |
|  2 | tank |  18 |  28000 | teacher |
|  3 | echo |  30 |  50000 | teacher |
|  4 | egon |  50 |   8000 | teacher |
+----+------+-----+--------+---------+
	1. 查看岗位是teacher的员工姓名、年龄
mysql> select name,age from teacher_info where job = 'teacher';
	2. 查看岗位是teacher且年龄大于30岁的员工姓名、年龄
mysql> select name,age from teacher_info where age >30;
+------+-----+
| name | age |
+------+-----+
| egon |  50 |
+------+-----+
1 row in set (0.00 sec)

	3. 查看岗位是teacher且薪资在5000-10000范围内的员工姓名、年龄、薪资
mysql> select name,age,salary from teacher_info where job = 'teacher' and (salary between 5000 and 10000);
+------+-----+--------+
| name | age | salary |
+------+-----+--------+
| egon |  50 |   8000 |
+------+-----+--------+
1 row in set (0.00 sec)
	4. 查看岗位描述不为NULL的员工信息
mysql> select * from teacher_info where job != null;
Empty set (0.00 sec)
	5. 查看岗位是teacher且薪资是10000或8000或30000的员工姓名、年龄、薪资
mysql> select name,age,salary from teacher_info where salary in (10000,8000,30000);
+------+-----+--------+
| name | age | salary |
+------+-----+--------+
| nick |  18 |  30000 |
| egon |  50 |   8000 |
+------+-----+--------+
2 rows in set (0.33 sec)
	6. 查看岗位是teacher且薪资不是10000或8000或30000的员工姓名、年龄、薪资
mysql> select name,age,salary from teacher_info where salary not in (10000,8000,30000);
+------+-----+--------+
| name | age | salary |
+------+-----+--------+
| tank |  18 |  28000 |
| echo |  30 |  50000 |
+------+-----+--------+
2 rows in set (0.00 sec)
	7. 查看岗位是teacher且名字是jin开头的员工姓名、年薪
mysql> select name,salary from teacher_info where name = 'jin%';
Empty set (0.00 sec)