Question

我的数据库表

StudId Day1 Day2 Day3 Day4 Day5
-------------------------------
1       P    P    P    P    P
2       A    P    P    P    P
3       P    A    P    A    P
4       A    P    P    P    P

我希望每个studentId的数据

       1
Day1   P 
Day2   P
Day3   P
Day4   P
Day5   P

我该如何实现这个场景？请帮帮....

Answer 1

为每列使用'allion all'：

假设结果列将被称为'col1'而不是'1'

Select Day1 as 'col1'
From table
Where StudId = 1

 Union all

select Day2 as  'col1'
From table
Where StudId = 1

--and so on

Answer 2

试，

declare @tb table (StudId int, Day1 char, Day2 char, Day3 char, Day4 char, Day5 char)
insert into @tb (StudId, Day1, Day2, Day3, Day4, Day5) values
(1,'P','P','P','P','P'),
(2,'A','P','P','P','P'),
(3,'P','A','P','A','P'),
(4,'A','P','P','P','P')
select cat,[1],[2],[3],[4] from(

select  t.* from @tb cross apply( values (StudId,Day1,'day1'),(StudId,Day2,'day2'),(StudId,Day3,'day3'),(StudId,Day4,'day4'),(StudId,Day5,'day5')) t (StudId,value,cat)) t
pivot
( min(value) for studid in ([1],[2],[3],[4])
)pvt

将我的行转换为列数据，将列转换为sql server中的行

2 个答案: