SQL交叉表的实例(横表转纵表)

--建表SQL
CREATE TABLE [Test] 
(
    [id] [int] IDENTITY (1, 1)  primary key,
    [name] [nvarchar] (50) ,
    [subject] [nvarchar] (50),
    [Source] int,
)ON [PRIMARY]
GO
INSERT INTO [test] ([name],[subject],[Source]) values (N'张三',N'语文',60)
INSERT INTO [test] ([name],[subject],[Source]) values (N'李四',N'数学',70)
INSERT INTO [test] ([name],[subject],[Source]) values (N'王五',N'英语',80)
INSERT INTO [test] ([name],[subject],[Source]) values (N'王五',N'数学',75)
INSERT INTO [test] ([name],[subject],[Source]) values (N'王五',N'语文',57)
INSERT INTO [test] ([name],[subject],[Source]) values (N'李四',N'语文',80) 
INSERT INTO [test] ([name],[subject],[Source]) values (N'张三',N'英语',100)
Go
--交叉表语句实现
--方式1：交叉表的列数是确定的
select name,sum(case [subject] when '数学' then [Source] else 0 end) as '数学',
            sum(case [subject] when '语文' then [Source] else 0 end) as '语文',
            sum(case [subject] when '英语' then [Source] else 0 end) as '英语'
from [test] 
group by name

--方式2：交叉表的列数是不确定的
declare @sql varchar(8000)
set @sql = 'select name,'
select @sql = @sql + 'sum(case subject when '''+[subject]
+'''then source else 0 end) as '+[subject]+',' from (select distinct [subject] from test) as a
select @sql = left(@sql,len(@sql)-1) + ' from test group by name'
exec(@sql)
go