使用大小寫和總結語句更新

Question

運行此查詢後，我收到一條錯誤消息，提示無效使用組函數。我很確定它的案例陳述後，我需要一個「AS量」或「AS i.amount」，但mySQl不喜歡任何這些。有什麼建議麼？

update INVITATION AS i 
LEFT JOIN REGISTRATION AS r on i.id=r.INVITATION_id 
LEFT JOIN FUNDING AS f on r.id=f.REGISTRATION_id 
SET i.funding_travel_amount = SUM(case 
when f.category = "Other" then sum(amount) 
when f.category = "Airfare" then sum(amount) 
when f.category = "Mileage" then sum(amount) 
else 0 end), i.funding_travel = "Custom" 
WHERE i.funding_hotel = "Prepaid" 
and i.funding_travel = "None" 
and i.funding_per_diem = "None" 
and (f.category = "Other" OR f.category ="Airfare" OR f.category= "Mileage") 
and f.id is not null; 

Answer 1

這是您的查詢格式化，因此更具有可讀性（至少對我來說）：

update INVITATION i LEFT JOIN 
     REGISTRATION r 
     on i.id=r.INVITATION_id LEFT JOIN 
     FUNDING AS f on r.id=f.REGISTRATION_id 
    SET i.funding_travel_amount = 
      SUM(case when f.category = "Other" then sum(amount) 
        when f.category = "Airfare" then sum(amount) 
        when f.category = "Mileage" then sum(amount) 
        else 0 
       end), 
     i.funding_travel = "Custom" 
    WHERE i.funding_hotel = "Prepaid" and 
      i.funding_travel = "None" and 
      i.funding_per_diem = "None" and 
      (f.category = "Other" OR f.category ="Airfare" OR f.category= "Mileage") and 
      f.id is not null; 

Onee問題是顯而易見的 - 你有資金內和報表。我將與相關子查詢寫：

update INVITATION 
    SET funding_travel_amount = 
      (select SUM(case when f.category = "Other" then amount 
          when f.category = "Airfare" then amount 
          when f.category = "Mileage" then amount 
          else 0 
         end) 
      from Registration r join 
        Funding f 
        on r.id=f.REGISTRATION_id and 
        invitation.id = r.invitation_id 
      ), 
     funding_travel = "Custom" 
    WHERE funding_hotel = "Prepaid" and 
      funding_travel = "None" and 
      funding_per_diem = "None" 

這是不完全一樣的，因爲它甚至會更新量時沒有類別是avaialble。你可以在where上附加一個條件來解決這個問題。

Answer 2

也許，你應該量之前刪除總和。