使用動態SQL

Question

即時嘗試從我的表中返回一個矩陣。 我的兩個表如下所示：

**Employe_Course_Instance** 
PersonNumber Year Period CourseCode Hour 
111   2015 3  a1   10 
222   2016 4  a2   4 
333   2018 2  a3   8 
444   2015 1  a4   5 

**Employe** 
PersonNumber FirstName LastName Salary Type 
    111   A  LA  100 teacher 
    222   B  LB  120 teacher 
    333   C  LC  150 teacher 
    444   D  LD  120 teacher 

我需要一個表是這樣的： 其中CourseCode和週期會像CourseCode /週期表中的數據，且只能包含4個時期。在CourseCode/Period中以行顯示薪水。

FirstName LastName a1/3 a2/4 a3/2 a4/1 Hours 
    A   LA 100     10 
    B   LB   120    4 
    C   LC    150  8 
    D   LD     120 5 

，這是我嘗試做這個 - >

declare @ColumnNames nvarchar(max) 
declare @SQL nvarchar(max) 

set @SQL = '' 
set @ColumnNames = '' 
select @ColumnNames = @ColumnNames + quotename (coursecode) + ',' 
from bemaning 

set @ColumnNames = left (@ColumnNames, len (@ColumnNames) - 1) 

print @ColumnNames 

set @SQL = 
'select * from 
(select 
employe.firsname, employe.lastname, 
Employe_Course_Instance.coursecode + ''/'' + CAST(Employe_Course_Instance.period as varchar (50)) as CourseCode_Period, 
Employe_Course_Instance.year, Employe_Course_Instance.hours 
from 
employe inner join Employe_Course_Instance on employe.personnumber = Employe_Course_Instance.personnumber) 


pivot(
    sum(hour) 
    for CourseCode_Period in (' + @ColumnNames +') 

) as pivot_table' 

--print @SQL 
execute sp_executesql @SQL 

我GET-錯誤>

Msg 156, Level 15, State 1, Line 10 
Incorrect syntax near the keyword 'pivot'. 

Answer 1

您需要FROM語句後添加一個alias

AS <alias for the source query> 

。於是，具有

select * from 
(select 
employe.firsname, employe.lastname, 
Employe_Course_Instance.coursecode + ''/'' + 
CAST(Employe_Course_Instance.period as varchar (50)) as CourseCode_Period, 
Employe_Course_Instance.year, Employe_Course_Instance.hours 
from 
employe inner join Employe_Course_Instance on employe.personnumber = 
Employe_Course_Instance.personnumber) AS pvtTable 

pivot(

PIVOT documentation

Answer 2

是的，那是因爲你缺少你的直列一個table alias視圖。它應該像

on employe.personnumber = Employe_Course_Instance.personnumber) XXX 
                   ^... Here 
pivot(
sum(hour) 
for CourseCode_Period in (' + @ColumnNames +') 
.....