折叠每行的空白列

Question

我有一张从Excel电子表格导入的大表格。对于包含教师姓名的五列，我想折叠每行中的所有空白，所以我没有任何姓名左侧的空白。一个例子可能会更好地表明我的意思。

这里的数据的例子现在：

Student ID Teacher1 Teacher2 Teacher3 Teacher4 Teacher5 
445633  Mary    Deb  Juan 
876302  Trevor Juan  Mary  Val  Deb 
659404  Luo          Trevor 
535485       Deb  
775431    Val       Luo 
565002    Luo  Mary    Juan 

而且我想空白崩溃的左侧，所以它看起来是这样的：

Student ID Teacher1 Teacher2 Teacher3 Teacher4 Teacher5 
445633  Mary  Deb  Juan  
876302  Trevor Juan  Mary  Val  Deb 
659404  Luo  Trevor  
535485  Deb   
775431  Val  Luo  
565002  Luo  Mary  Juan 

我必须这样做这种方式是因为我将它粘贴到一个国家规定的Excel模板中，而且我无法在教师姓名的左边留下任何空白，只有空白才是正确的。

谢谢！

Answer 1

您可以逆透视，ROW_NUMBER（）在教师和枢轴再次...那就是：

declare @t1 as table (StudentID int, Teacher1 nvarchar(100), Teacher2 nvarchar(100), Teacher3 nvarchar(100), Teacher4 nvarchar(100), Teacher5 nvarchar(100)); 
insert into @t1 values (445633,'Mary',NULL,'Deb','Juan',NULL),(876302,'Trevor','Juan','Mary','Val','Deb'), 
(659404,'Luo',NULL,NULL,NULL,'Trevor'),(535485,NULL,NULL,NULL,'Deb',NULL), 
(775431,NULL,NULL,'Val',NULL,'Luo'),(565002,NULL,NULL,'Luo','Mary','Juan'); 

with UnpivotT as (
    SELECT StudentID, TeacherName, TeacherColumn as OriginalColumn 
    from @t1 unpivot (
     TeacherName for TeacherColumn in ([Teacher1],[Teacher2],[Teacher3],[Teacher4],[Teacher5]) 
    ) uT 
), NewColumnT as (
    select StudentID, TeacherName, 'Teacher'+(
      convert(nvarchar(100), ROW_NUMBER() OVER (PARTITION BY StudentID ORDER BY OriginalColumn)) 
     ) as NewColumn 
    from UnpivotT 
) 
select * 
from NewColumnT 
pivot (
    max(TeacherName) for NewColumn in ([Teacher1],[Teacher2],[Teacher3],[Teacher4],[Teacher5]) 
) as pivotT