行列转换的例子

IF OBJECT_ID(‘tempdb..#ABC‘) IS NOT NULL
DROP TABLE #ABC  

create table #ABC
(
ID  INT
,UserID BIGINT
,UserExamID INT
,TestPaperID INT
,QuestionID INT
,AnswerID   INT
,Ctime DATETIME
)
INSERT INTO #ABC
SELECT 1,120629210042331600,1,3,22,49,GETDATE() UNION ALL
SELECT 2,120629210042331600,1,3,23,51,GETDATE() UNION ALL
SELECT 3,120629210042331600,1,3,24,56,GETDATE() UNION ALL
SELECT 4,120629210042331600,1,3,25,62,GETDATE() UNION ALL
SELECT 5,120629210042331600,1,3,26,66,GETDATE() UNION ALL
SELECT 6,120629210042331600,1,3,27,72,GETDATE() UNION ALL
SELECT 7,120629210042331600,1,3,28,77,GETDATE() UNION ALL
SELECT 8,120629210042331600,1,3,29,81,GETDATE() UNION ALL
SELECT 9,120629210042331600,1,3,30,86,GETDATE() UNION ALL
SELECT 10,120629210042331600,1,3,31,90,GETDATE() UNION ALL
SELECT 1,120629210011732588,1,3,22,49,GETDATE() UNION ALL
SELECT 2,120629210011732588,1,3,23,51,GETDATE() UNION ALL
SELECT 3,120629210011732588,1,3,24,56,GETDATE() UNION ALL
SELECT 4,120629210011732588,1,3,25,62,GETDATE() UNION ALL
SELECT 5,120629210011732588,1,3,26,66,GETDATE() UNION ALL
SELECT 6,120629210011732588,1,3,27,72,GETDATE() UNION ALL
SELECT 7,120629210011732588,1,3,28,77,GETDATE() UNION ALL
SELECT 8,120629210011732588,1,3,29,81,GETDATE() UNION ALL
SELECT 9,120629210011732588,1,3,30,86,GETDATE() UNION ALL
SELECT 10,120629210011732588,1,3,31,90,GETDATE()    

SELECT * FROM #ABC  

DECLARE @s NVARCHAR(4000)
SELECT @s = ISNULL(@s + ‘,‘, ‘‘) +  QUOTENAME(QuestionID)
FROM  (select distinct QuestionID from #ABC) as A ---列名不要重复  

Declare @sql NVARCHAR(4000)
SET @sql=‘
 select r.* from
(select UserID,QuestionID,AnswerID from #ABC) as t
pivot
(
max(t.AnswerID)
for t.QuestionID in (‘+@s+‘)
) as r‘  

EXEC( @sql) 

如果要消除NULL，可以利用@s构造一个 ISNULL(字段.0) AS [字段]