出錯創建視圖（View的SELECT包含在FROM子句中的子查詢）請建議對這段代碼

Question

我得到以下錯誤而創建視圖

備用選項或方法

視圖的SELECT語句包含在子查詢FROM子句

請建議爲這一段代碼

Create or Replace view mydb.cnCustomerv 
as 
Select * from mydb.customermaster 
left join 
(
    Select customertransaction.transactioninvoiceno , customertransaction.transactionvalue , customertransaction.cardnumber from mydb.customertransaction order by customertransaction.transactionid desc limit 1 
) as a on 
mydb.customermaster.cardnumber = a.cardnumber 
left join 
(
    Select customerredemption.transactionuniquecode , customerredemption.redemptionvalue , customerredemption.cardnumber from mydb.customerredemption order by customerredemption.redemptionid desc limit 1 
) as B on 
mydb.customermaster.cardnumber = B.cardnumber; 

Answer 1

替代選項或方法根據手冊，VIEW不能包含子查詢。如果您想在查詢中創建VIEW，則需要爲您的子查詢創建單獨的視圖。

首先查看

Create or Replace VIEW mydb.CTView 
AS 
Select ct.transactioninvoiceno, ct.transactionvalue, ct.cardnumber 
from mydb.customertransaction ct order by ct.transactionid desc limit 1 

第二個視圖

Create or Replace VIEW mydb.CRView 
AS 
Select cr.transactionuniquecode, cr.redemptionvalue, cr.cardnumber 
from mydb.customerredemption cr order by cr.redemptionid desc limit 1 

主視圖，

Create or Replace view mydb.cnCustomerv 
as 
Select * from mydb.customermaster 
left join mydb.CTView as a on mydb.customermaster.cardnumber = a.cardnumber 
left join mydb.CRView as B on mydb.customermaster.cardnumber = B.cardnumber; 

A view definition is subject to the following restrictions：從MySQL手冊

• SELECT語句不能在FROM子句中包含子查詢。
• ....