我正在努力想弄清楚如何在SQL Server 2008中使用多列进行动态数据透视。
我的样本表如下：
ID YEAR TYPE TOTAL VOLUME
DD1 2008 A 1000 10
DD1 2008 B 2000 20
DD1 2008 C 3000 30
DD1 2009 A 4000 40
DD1 2009 B 5000 50
DD1 2009 C 6000 60
DD2 2008 A 7000 70
DD2 2008 B 8000 80
DD2 2008 C 9000 90
DD2 2009 A 10000 100
DD2 2009 B 11000 110
DD2 2009 C 12000 120
我正在尝试如下：
ID 2008_A_TOTAL 2008_A_VOLUME 2008_B_TOTAL 2008_B_VOLUME 2008_C_TOTAL 2008_C_VOLUME 2009_A_TOTAL 2009_A_VOLUME 2009_B_TOTAL 2009_B_VOLUME 2009_C_TOTAL 2009_C_VOLUME
DD1 1000 10 2000 20 3000 30 4000 40 5000 50 6000 60
DD2 7000 70 8000 80 9000 90 10000 100 11000 110 12000 120
我的SQL Server 2008查询如下创建表：
CREATE TABLE ATM_TRANSACTIONS
(
ID varchar(5),
T_YEAR varchar(4),
T_TYPE varchar(3),
TOTAL int,
VOLUME int
);
INSERT INTO ATM_TRANSACTIONS
(ID,T_YEAR,T_TYPE,TOTAL,VOLUME)
VALUES
('DD1','2008','A',1000,10),
('DD1','2008','B',2000,20),
('DD1','2008','C',3000,30),
('DD1','2009','A',4000,40),
('DD1','2009','B',5000,50),
('DD1','2009','C',6000,60),
('DD2','2008','A',7000,70),
('DD2','2008','B',8000,80),
('DD2','2008','C',9000,90),
('DD2','2009','A',10000,100),
('DD2','2009','B',11000,110),
('DD2','2009','C',1200,120);
T_Year列可能会在将来发生变化，但T_TYPE列通常都知道，所以我不确定我是否可以将SQL Server中的PIVOT函数与动态代码结合使用？
我尝试了以下示例：
但我最终得到了奇怪的结果。
答案 0 :(得分：18)
为了获得结果，在应用PIVOT函数获取最终结果之前，您需要先查看Total和Volume列中的数据的取消隐藏。我的建议是首先编写查询的硬编码版本，然后将其转换为动态SQL。
UNPIVOT进程将这些多列转换为行。有几种方法可以使用UNPIVOT，你可以使用UNPIVOT功能，也可以使用CROSS APPLY。取消数据的代码类似于：
select id,
col = cast(t_year as varchar(4))+'_'+t_type+'_'+col,
value
from ATM_TRANSACTIONS t
cross apply
(
select 'total', total union all
select 'volume', volume
) c (col, value);
这将为您提供以下格式的数据：
+-----+---------------+-------+
| id | col | value |
+-----+---------------+-------+
| DD1 | 2008_A_total | 1000 |
| DD1 | 2008_A_volume | 10 |
| DD1 | 2008_B_total | 2000 |
| DD1 | 2008_B_volume | 20 |
| DD1 | 2008_C_total | 3000 |
| DD1 | 2008_C_volume | 30 |
+-----+---------------+-------+
然后你可以应用PIVOT功能：
select ID,
[2008_A_total], [2008_A_volume], [2008_B_total], [2008_B_volume],
[2008_C_total], [2008_C_volume], [2009_A_total], [2009_A_volume]
from
(
select id,
col = cast(t_year as varchar(4))+'_'+t_type+'_'+col,
value
from ATM_TRANSACTIONS t
cross apply
(
select 'total', total union all
select 'volume', volume
) c (col, value)
) d
pivot
(
max(value)
for col in ([2008_A_total], [2008_A_volume], [2008_B_total], [2008_B_volume],
[2008_C_total], [2008_C_volume], [2009_A_total], [2009_A_volume])
) piv;
现在您拥有了正确的逻辑，您可以将其转换为动态SQL：
DECLARE @cols AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX)
select @cols = STUFF((SELECT ',' + QUOTENAME(cast(t_year as varchar(4))+'_'+t_type+'_'+col)
from ATM_TRANSACTIONS t
cross apply
(
select 'total', 1 union all
select 'volume', 2
) c (col, so)
group by col, so, T_TYPE, T_YEAR
order by T_YEAR, T_TYPE, so
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'')
set @query = 'SELECT id,' + @cols + '
from
(
select id,
col = cast(t_year as varchar(4))+''_''+t_type+''_''+col,
value
from ATM_TRANSACTIONS t
cross apply
(
select ''total'', total union all
select ''volume'', volume
) c (col, value)
) x
pivot
(
max(value)
for col in (' + @cols + ')
) p '
execute sp_executesql @query;
这会给你一个结果：
+-----+--------------+---------------+--------------+---------------+--------------+---------------+--------------+---------------+--------------+---------------+--------------+---------------+
| id | 2008_A_total | 2008_A_volume | 2008_B_total | 2008_B_volume | 2008_C_total | 2008_C_volume | 2009_A_total | 2009_A_volume | 2009_B_total | 2009_B_volume | 2009_C_total | 2009_C_volume |
+-----+--------------+---------------+--------------+---------------+--------------+---------------+--------------+---------------+--------------+---------------+--------------+---------------+
| DD1 | 1000 | 10 | 2000 | 20 | 3000 | 30 | 4000 | 40 | 5000 | 50 | 6000 | 60 |
| DD2 | 7000 | 70 | 8000 | 80 | 9000 | 90 | 10000 | 100 | 11000 | 110 | 1200 | 120 |
+-----+--------------+---------------+--------------+---------------+--------------+---------------+--------------+---------------+--------------+---------------+--------------+---------------+
答案 1 :(得分：2)
declare @stmt nvarchar(max)
select @stmt = isnull(@stmt + ', ', '') +
'sum(case when T_YEAR = ''' + T.T_YEAR + ''' and T_TYPE = ''' + T.T_TYPE + ''' then TOTAL else 0 end) as ' + quotename(T.T_YEAR + '_' + T.T_TYPE + '_TOTAL') + ',' +
'sum(case when T_YEAR = ''' + T.T_YEAR + ''' and T_TYPE = ''' + T.T_TYPE + ''' then VOLUME else 0 end) as ' + quotename(T.T_YEAR + '_' + T.T_TYPE + '_VOLUME')
from (select distinct T_YEAR, T_TYPE from ATM_TRANSACTIONS) as T
order by T_YEAR, T_TYPE
select @stmt = '
select
ID, ' + @stmt + ' from ATM_TRANSACTIONS group by ID'
exec sp_executesql
@stmt = @stmt
不幸的是，sqlfiddle.com目前还没有工作，所以我无法为你创建一个例子。
动态SQL创建的查询将是：
select
ID,
sum(case when T_YEAR = '2008' and T_TYPE = 'A' then TOTAL else 0 end) as 2008_A_TOTAL,
sum(case when T_YEAR = '2008' and T_TYPE = 'A' then VOLUME else 0 end) as 2008_A_VOLUME,
...
from ATM_TRANSACTIONS
group by ID
答案 2 :(得分：0)
请尝试：
DECLARE @pivv NVARCHAR(MAX),@Query NVARCHAR(MAX)
SELECT @pivv=COALESCE(@pivv+',','')+ QUOTENAME(T_YEAR+'_'+T_TYPE+'_TOTAL')+','+QUOTENAME(T_YEAR+'_'+T_TYPE+'_VOLUME') from ATM_TRANSACTIONS GROUP BY T_YEAR, T_TYPE
IF ISNULL(@pivv, '')<>''
SET @Query='SELECT * FROM(
SELECT ID, T_YEAR+''_''+T_TYPE+''_TOTAL'' TYP, TOTAL VAL from ATM_TRANSACTIONS UNION
SELECT ID, T_YEAR+''_''+T_TYPE+''_VOLUME'' TYP, VOLUME VAL from ATM_TRANSACTIONS
)x pivot (SUM(VAL) for TYP in ('+@pivv+')) as xx'
IF ISNULL(@Query, '')<>''
EXEC (@Query)