T-SQL的動態透視不同和多列

表學生：T-SQL的動態透視不同和多列

Studid  StuName  
========================= 
1   'Marco Polo' 
2   'Leroy Jenkins'

表主題：

Subid  SubName  
=================== 
1   English 
2   French 
3   German 
4   Math 
5   Physics

表等級

Stuid  Subid   Grade1   Grade2 
================================================== 
1   1    10    6  
1   2    9    7  
2   1    8    4  
2   4    7    9  
2   5    6    10

我想實現2個表：表1：

StuName  English 1  English 2  French 1  French 2 
================================================================== 
'Marco Polo'  10    6    9    7

表1：

StuName  English 1  English 2  Math 1  Math 2  Physics 1  Physics 2 
================================================================== 
'Leroy Jenkins' 8    4    7    9 6    10

來源

2017-07-07 assmokey

的問題是，樂華是要趕在之前，你甚至寫完您的查詢。 – SqlZim

關於你的預期結果應該是什麼不是很清楚。另外，你能否提供你迄今爲止所嘗試的？ – gh0st

我沒有嘗試任何事情，我不知道，因爲通知，字段的數量是一個時間5，另一個是7 – assmokey

在您的例子在Student的ID是StudId和Grades這是StuId。這可能是也可能不是一個錯字，但是我把它作爲張貼留下。

您需要unpivot主題+ gradenumber（我用的是cross apply(values...)方法unpivot在下面的代碼，但一個union all或unpivot()版本將工作爲好），然後轉動。

既然你只是想返回特定於每一個學生列，您使用的列列表生成，並在pivot的內部查詢的過濾器和參數傳遞給sp_executesql爲生成的代碼的執行。

declare @cols nvarchar(max), @sql nvarchar(max), @StuId int; 
set @StuId = 2; 
set @cols = stuff((
    select ', ' + quotename(sub.subName+'1')+', '+ quotename(sub.subName+'2') 
    from Grades g 
     inner join Student stu 
     on g.StuId = stu.StudId 
     inner join Subjects sub 
     on g.SubId = sub.SubId 
    where stu.StudId = @StuId 
    order by 1 
    for xml path (''), type).value('(./text())[1]','nvarchar(max)') 
    ,1,2,''); 
set @sql = ' 
    select StuName, '+ @cols +' 
    from (
     select stu.StuName, u.SubName, u.Grade 
     from Grades g 
     inner join Student stu 
      on g.StuId = stu.StudId 
     inner join Subjects sub 
      on g.SubId = sub.SubId 
     cross apply (values 
      (sub.SubName+''1'', g.Grade1) 
      , (sub.SubName+''2'', g.Grade2) 
     )u (SubName,Grade) 
     where stu.StudId = @StuId 
    ) as t 
    pivot (sum(Grade) for SubName in (' + @cols +')) p'; 

select CodeGenerated = @sql; 
exec sp_executesql @sql ,N'@StuId int', @StuId;

rextester演示：http://rextester.com/DCLY81531

回報CodeGenerated：

select StuName, [English1], [English2], [Math1], [Math2], [Physics1], [Physics2] 
    from (
     select stu.StuName, u.SubName, u.Grade 
     from Grades g 
     inner join Student stu 
      on g.StuId = stu.StudId 
     inner join Subjects sub 
      on g.SubId = sub.SubId 
     cross apply (values 
      (sub.SubName+'1', g.Grade1) 
      , (sub.SubName+'2', g.Grade2) 
     )u (SubName,Grade) 
     where stu.StudId = @StuId 
    ) as t 
    pivot (sum(Grade) for SubName in ([English1], [English2], [Math1], [Math2], [Physics1], [Physics2])) p

爲@StuId = 2回報：

+---------------+----------+----------+-------+-------+----------+----------+ 
| StuName | English1 | English2 | Math1 | Math2 | Physics1 | Physics2 | 
+---------------+----------+----------+-------+-------+----------+----------+ 
| Leroy Jenkins |  8 |  4 |  7 |  9 |  6 |  10 | 
+---------------+----------+----------+-------+-------+----------+----------+

爲@StuId = 1回報：

+------------+----------+----------+---------+---------+ 
| StuName | English1 | English2 | French1 | French2 | 
+------------+----------+----------+---------+---------+ 
| Marco Polo |  10 |  6 |  9 |  7 | 
+------------+----------+----------+---------+---------+

來源

2017-07-07 17:06:21 SqlZim

Studid是一個錯字，這是Stuid。謝謝你的答案，標記爲正確的答案。 – assmokey

@assmokey樂於助人！ – SqlZim

T-SQL的動態透視不同和多列

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