為什么在MS Access中有效的SQL查詢在SQL Server中不起作用？

Question

以下查詢在MS Access中有效，但在MS SQL Server中不起作用：

SELECT
  tblSession.PatientID as PID,
  max(tblSession.SessionAttend) - 
    min(tblSession.SessionAttend) + 1 as NumSA,
  max(tblSession.SessionSched) - 
    min(tblSession.SessionSched) + 1 as NumSS FROM
  (
    SELECT top 100 percent
      tblSession.PatientID,
      tblSession.SessionNumber,
      tblSession.SessionDate,
      tblSession.SessionAttend,
      tblSession.SessionSched FROM
      tblPatient INNER JOIN tblSession ON
        tblPatient.PatientID = tblSession.PatientID) WHERE
        (tblSession.SessionDate >= '12/8/2010') AND
        (tblSession.SessionDate <= '5/18/2011') AND
        (tblSession.Status = '2') ORDER BY 
          tblSession.PatientID, tblSession.SessionNumber
  ) GROUP BY tblSession.PatientID

在SQL Server中，它提供錯誤“關鍵字'GROUP'附近的語法不正確。” 當我將鼠標懸停在GROUP關鍵字上時，工具提示會顯示“GROUP'附近的語法錯誤。期望AS，ID或QUOTED_ID。” 我不明白。 誰能告訴我如何使這個查詢工作？

Answer 1

()的派生表需要一個別名，並且SELECT列表中的列引用也相應地更新：

SELECT top 100 percent
  ALIASNAME.PatientID as PID,
  max(ALIASNAME.SessionAttend) - 
    min(ALIASNAME.SessionAttend) + 1 as NumSA,
  max(ALIASNAME.SessionSched) - 
    min(ALIASNAME.SessionSched) + 1 as NumSS FROM
  (
    SELECT top 100 percent
      tblSession.PatientID,
      ...
      ...
      ...
      ...
          tblSession.PatientID, tblSession.SessionNumber
  -- This derived table needs an alias
  ) ALIASNAME 
  GROUP BY ALIASNAME.PatientID