将几个相同的行转换为相同的列答案

【问题标题】：Convert several identical rows into identical columns将几个相同的行转换为相同的列
【发布时间】：2018-05-11 20:22:57
【问题描述】：

以下可能吗？

我有一个包含 3 列（代码、案例编号、折扣）的表，其中包含这 6 行。

如何让输出为 Code、CaseNumber、Discount，其中“CaseNumber、Discount”重复相同的代码？

例如，对于上表，输出应该是

123 1 10 2 20 3 30
456 4 40 5 50 6 60

【问题讨论】：

你使用的是什么 rdbms？
@DanielMarcus MS SQL 2012

标签： sql row multiple-columns

【解决方案1】：

 select Code,  
 max(case when CaseNumber = 1 then CaseNumber end) as CaseNumber,
 max(case when CaseNumber = 2 then CaseNumber end) as CaseNumber,
 max(case when CaseNumber = 3 then CaseNumber end) as CaseNumber, 
 max(case when CaseNumber = 4 then CaseNumber end) as CaseNumber, 
 max(case when CaseNumber = 5 then CaseNumber end) as CaseNumber, 
 max(case when CaseNumber = 6 then CaseNumber end) as CaseNumber,
 max(case when Discount = 10 then Discount end) as Discount,
 max(case when Discount = 20 then Discount end) as Discount,
 max(case when Discount = 30 then Discount end) as Discount, 
 max(case when Discount = 40 then Discount end) as Discount, 
 max(case when Discount = 50 then Discount end) as Discount, 
 max(case when Discount = 60 then Discount end) as Discount     
 from
 (
 select * , row_number() over(partition by Code order by Code) rn
 from yourTable
 ) s
 group by Code
 go

【讨论】：

无法硬编码案件编号或金额，因为它们总是因不同的代码和每个月而异。
如果你可以使用SQL Server，这很容易解决
@DanielMarcus 我确实使用 SQL Server，如何使用 T-SQL 完成此操作？
动态 sql - 明天将尝试为您执行此操作

【解决方案2】：

假设您的原始表是#temp:

declare @final table (rowid int identity, string varchar(max))

declare @holding table (Code int, CaseNumber int, Discount int, rownum int) 
insert @holding 
select *, row_number() over(partition by code order by code) from #temp 

--select * from @holding

declare @string varchar(max)=''
--declare @string2 varchar(max)=''
declare @code int = (select min(code) from @holding)
declare @casenumber int
declare @discount int
declare @iterator int = 1
while @code<=(select max(code) from @holding)
--select @string=  @code','
begin 
while @iterator<=(select max(rownum) from @holding where code=@code)
begin
select @casenumber=  casenumber , @discount=discount from @holding where code=@code and  @iterator=rownum
select @string=@string+','+cast(@casenumber as varchar(max))+','+cast(@discount as varchar(max))
set @iterator=@iterator+1
end
insert @final
select cast(@code as varchar(max))+@string
select @code=min(code) from @holding where code>@code
set @iterator=1
set @string=''
end 

set @iterator=1
set @string=''
declare @string2 varchar(max)=''
while @iterator<=(select max(rowid) from @final)
begin
select @string2 = string from @final where rowid=@iterator
select @string= case when @iterator <(select max(rowid) from @final) then 
@string+' select '+@string2+ ' union all '  else @string+' select '+@string2 end 
set @iterator=@iterator+1

end 

exec(''+@string+'')

【讨论】：