R
distinct去除重複的數據
基礎查詢
1
2
3
4
5
6
7
8
9
10
11
12
--查詢所有列、所有行
select * from Department
select * from [Rank]
select * from Employee
--查詢指定列(姓名、性別、生日、月薪、電話)
select EmployeeName, EmployeeSex, EmployeeBirth, EmployeeSalary, EmployeePhone from Employee
--查詢指定列(姓名、性別、生日、月薪、電話)(顯示中文列名)
select EmployeeName 姓別, EmployeeSex 性別, EmployeeBirth 生日, EmployeeSalary 月薪, EmployeePhone 月薪 from Employee --as可以省略
--查詢出員工所在的城市(去除重複數據 distinct)
select distinct EmployeeAddress from Employee
--假設準備加工資(上調20%)，查詢出加工資前&加工資後的數據對比的員工數據
select EmployeeName, EmployeeSex, EmployeeSalary, EmployeeSalary * 1.2 加薪後工資 from Employee