嵌套連接隱藏表名

Question

我有三個表：供應商，零件和類型。我需要加入他們所有的人，同時區分三個表中同名的列（比如「id」）。我想成功運行此查詢：

CREATE VIEW Everything AS 
SELECT Suppliers.name as supplier, 
     Parts.id, 
     Parts.description, 
     Types.typedesc as type 
FROM Suppliers JOIN (Parts JOIN Types ON Parts.type_id = Types.id) 
ON Suppliers.id = Parts.supplier_id; 

我DBMS（sqlite的）抱怨說，「沒有這樣的列（Parts.id）」。我猜想一旦JOIN完成後它會忘記表名，但是我怎麼能參考屬於表Parts的列id？

Answer 1

你的ANSI-92 JOIN語法不正確 - 使用：

CREATE VIEW Everything AS 
    SELECT Suppliers.name as supplier, 
     Parts.id, 
     Parts.description, 
     Types.typedesc as type 
    FROM Suppliers 
    JOIN Parts ON Suppliers.id = Parts.supplier_id 
    JOIN Types ON Parts.type_id = Types.id 

Answer 2

只要你在排位賽聯接基於表Alias.Field名字，你應該沒有問題......比如

CREATE VIEW Everything AS 
     SELECT 
      Suppliers.name as supplier, 
      Parts.id, 
      Parts.description, 
      Types.typedesc as type 
     FROM 
      Suppliers, 
      Parts, 
      Types 
     WHERE 
       Supplier.ID = Parts.Supplier_ID 
      AND Parts.Type_ID = Types.ID 
     ORDER BY 
      (whatever columns)