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sql列轉行

   CREATE TABLE [Test] (

  [id] [int] IDENTITY (1, 1) NOT NULL ,

  [name] [nvarchar] (50) COLLATE Chinese_PRC_CI_AS NULL ,

  [subject] [nvarchar] (50) COLLATE Chinese_PRC_CI_AS NULL ,

  [Source] [numeric](18, 0) NULL

  ) ON [PRIMARY]

  GO

  INSERT INTO [test] ([name],[subject],[Source]) values (N'張三',N'語文',60)

  INSERT INTO [test] ([name],[subject],[Source]) values (N'李四',N'數學',70)

  INSERT INTO [test] ([name],[subject],[Source]) values (N'王五',N'英語',80)

  INSERT INTO [test] ([name],[subject],[Source]) values (N'王五',N'數學',75)

  INSERT INTO [test] ([name],[subject],[Source]) values (N'王五',N'語文',57)

  INSERT INTO [test] ([name],[subject],[Source]) values (N'李四',N'語文',80)

  INSERT INTO [test] ([name],[subject],[Source]) values (N'張三',N'英語',100)

  Go

  --交叉表語句的實現:

  --用於:交叉表的列數是確定的

  select name,sum(case subject when '數學' then source else 0 end) as '數學',

  sum(case subject when '英語' then source else 0 end) as '英語',

  sum(case subject when '語文' then source else 0 end) as '語文'

  from test

  group by name

  --用於:交叉表的列數是不確定的

  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

  --用於:交叉表的列數是不確定的

  declare @sql varchar(8000)

  set @sql = 'select id,'

  select @sql = @sql + '(case subject when '''+subject+'''

  then source else null end) as '''+subject+''','

  from (select distinct subject from test) as a

  select @sql = left(@sql,len(@sql)-1) + ' from test '

  exec(@sql)

  go

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