如何将行转换为列？

Question

可能是一个简单的，有没有办法快速转置我的数据，以便它读取而不是按行读取。

以上是电流输出，但希望它跨越例如读取

AttendanceNumber, ExamDate, ExamCode1, ExamCode2, ExamCode3, .......ExamCode20 

我的SQL是

SELECT [AttendanceNumber] 
     ,[ExaminationDate] 
     ,[ExamExaminationCode] 
    FROM [Radiotherapy].[dbo].[tblRadiologyData] rd 
    where rd.ExaminationDate >= '01 april 2016' 
    and rd.AttendanceSiteCode IN('CNM','RNM') 
    ORDER BY rd.LocalPatientIdentifier, rd.ExaminationDate 

Answer 1

可以使用条件的聚集与ROW_NUMBER()：

SELECT s.attendanceNumber,s.examinationDate, 
     MAX(CASE WHEN s.rnk = 1 THEN s.ExamExaminationCode END) as examCode1, 
     MAX(CASE WHEN s.rnk = 2 THEN s.ExamExaminationCode END) as examCode2, 
     MAX(CASE WHEN s.rnk = 3 THEN s.ExamExaminationCode END) as examCode3, 
     ..... As many as you need 
FROM (
    SELECT [AttendanceNumber] 
      ,[ExaminationDate] 
      ,[ExamExaminationCode] 
      ,ROW_NUMBER() OVER(PARTITION BY [AttendanceNumber] ORDER BY [ExaminationDate]) as rnk --Ordered by date ASC 
     FROM [Radiotherapy].[dbo].[tblRadiologyData] rd 
     where rd.ExaminationDate >= '01 april 2016' 
     and rd.AttendanceSiteCode IN('CNM','RNM')) s 
GROUP BY s.attendanceNumber,s.examinationDate