Question

我的 sql 架构是这样的：sqlfiddle

我想显示TransactionID，DoctorID，PatientID和TotalMedicine（从每笔交易的MedicineID数量中获得），其中PatientID的最后3位数字是4的倍数。按医生ID递增数据排序，然后计算TotalMedicine是Doctor ID的最大，最小和平均。

我试过这个

SELECT th.TransactionID,
       th.DoctorID,
       th.PatientID,
       COUNT(td.MedicineID) AS TotalMedicine
FROM   TransactionHeader th
       JOIN TransactionDetail td
         ON th.TransactionID = td.TransactionID
WHERE  CAST(RIGHT(th.PatientID, 3) AS INT) % 4 = 0
GROUP  BY th.TransactionID,
          th.DoctorID,
          th.PatientID
ORDER  BY th.DoctorID ASC
COMPUTE max(COUNT(td.MedicineID)), 
        min(COUNT(td.MedicineID)), 
        avg(COUNT(td.MedicineID)) BY th.DoctorID

但它没有选择PatientID的最后3位数，它们是4的倍数。

Answer 1

假设您无法更改架构以向tableHeader提供varchar数据类型或char(5)，则需要考虑列末尾的空格。

RTRIM会是你想要的。

SELECT th.TransactionID,
       th.DoctorID,
       th.PatientID,
       COUNT(td.MedicineID) AS TotalMedicine
FROM   TransactionHeader th
       JOIN TransactionDetail td
         ON th.TransactionID = td.TransactionID
WHERE  CAST(RIGHT(RTRIM(th.PatientID), 3) AS INT) % 4 = 0
GROUP  BY th.TransactionID,
          th.DoctorID,
          th.PatientID
ORDER  BY th.DoctorID ASC

Answer 2

添加Where Cast(Substring(PatientId, Len(PatientId) - 2, 3) as Integer) % 4 = 0

Select TransactionID, DoctorID, PatientID, 
    Sum() TotalMedicine 
From TransactionHeader th
   JOIN TransactionDetail td
     ON th.TransactionID = td.TransactionID
Where Cast(Substring(PatientId, Len(PatientId) - 2, 3) as Integer) % 4 = 0
GROUP BY th.TransactionID,
      th.DoctorID,th.PatientID

SQL：如何选择最后3位数的列是4的倍数？

2 个答案: