SQL实验(实验4至实验7的答案) 下载本文

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SQL实验

实验4

1.用select 语句查询departments和salary表中的所有数据:

select salary.*, departments.* from salary ,departments

2、查询departments 中的departmentid:

select departmentid from departments go

3、查询 salary中的 income,outcome: select income,outcome from salary go

4、查询employees表中的部门号,性别,要用distinct消除重复行:

select distinct(departmentid), sex from employees

书籍是人类知识的总结,书籍是全世界的营养品。——莎士比亚

5、查询月收入高于2000元的员工号码:

select employeeid from salary where income>2000 go

6、查询1970年以后出生的员工的姓名和住址:

select name ,address from employees where birthday>1970 go

7、查询所有财务部的员工的号码和姓名:

select employeeid ,name from employees

where departmentid in(select departmentid from departments where

书籍是人类知识的总结,书籍是全世界的营养品。——莎士比亚

departmentname='财务部') go

8、查询employees员工的姓名,住址和收入水平,2000元以下显示为低收入,2000~3000元显示为中等收入,3000元以上显示为高收入:

select name ,address, case

when income-outcome<2000 then '低收入' when income-outcome>3000 then '高收入' else '中等收入'

end as '收入等级'

from employees,salary

where employees.employeeid=salary.employeeid go

9、计算salary表中员工月收入的评价数:

select avg(income)as '平均收入' from salary

10、查找employees表中最大的员工号码:

select max(employeeid)as '最大员工号码' from employees

11、计算salary表中的所有员工的总支出:

select sum(outcome) as'总支出' from salary

12、查询财务部雇员的最高实际收入:

select max(income-outcome) from salary ,employees,departments where salary.employeeid=employees.employeeid and

employees.departmentid=departments.departmentid and departmentname='财

书籍是人类知识的总结,书籍是全世界的营养品。——莎士比亚