Question

这是一个我知道的流行问题。我刚刚学习数据透视表，不知道我哪里出错了。

create table #test
(
     id varchar(4), 
     code varchar(2), 
     received_dt varchar(8)
)

insert into #test values ('1234','10','20150312')
insert into #test values ('1234','71','20150312')
insert into #test values ('1234','C5','20150312')
insert into #test values ('4321','10','20150312')
insert into #test values ('4321','71','20150312')
insert into #test values ('987','10','20150312')
insert into #test values ('987','71','20150312')
insert into #test values ('987','C5','20150312')

select id, [code1], [code2], [code3]
from #test
pivot(MAX(code) for code in ([code1], [code2], [code3])) as pvt

drop table #test

非常感谢任何帮助/指导。我知道这应该很容易，但我似乎无法将我的大脑包裹起来。

结果：

ID      Code1   Code2   Code3
1234    NULL    NULL    NULL
4321    NULL    NULL    NULL
987     NULL    NULL    NULL

想要：

ID      Code1   Code2   Code3
1234    10      71      C5
4321    10      71      NULL
987     10      71      C5

编辑有许多代码值。

Answer 1

您需要创建另一个包含Code1, Code2, Code3值的列：

;WITH CTE AS
(
    SELECT  *, 
            RN = 'Code' + 
                 CAST(ROW_NUMBER() OVER(PARTITION BY ID ORDER BY code) AS CHAR(1))
    FROM #test
)
SELECT id, [code1], [code2], [code3]
FROM CTE
PIVOT(MAX(code) for RN in ([code1], [code2], [code3])) as pvt;

<强>更新

如果您的代码数量未知，则需要动态SQL：

DECLARE @sql NVARCHAR(MAX) = N'', @cols NVARCHAR(MAX) = N'';

WITH CTE AS
(
    SELECT  *, 
            RN = 'Code' + 
                 CAST(ROW_NUMBER() OVER(PARTITION BY ID ORDER BY code) AS CHAR(1))
    FROM #test
)
SELECT @cols += STUFF((SELECT ',' + QUOTENAME(RN)
                       FROM CTE
                       GROUP BY RN
                       FOR XML PATH('')), 1, 1, '');


SET @sql = N'
SELECT *
FROM (  SELECT  *,
                RN = ''Code'' + 
                 CAST(ROW_NUMBER() OVER(PARTITION BY ID ORDER BY code) AS CHAR(1))
    FROM #test) AS d
PIVOT(MAX(code) for RN in (' + @cols + ')) AS p;';

EXEC sp_executesql @sql;

SQL Server数据透视表，空结果

1 个答案: