一个视图中有多个表？

Question

今天我的问题是我将如何去创建一个使用两个以上表的MySQL数据库的视图？

这是我的查询（它的工作原理）我不想改变我目前的查询，主要是寻找一个很好的参考与这个主题的例子。

CREATE OR REPLACE VIEW vw_itemsPurchased AS 
SELECT `tbl_buyers`.`fldPrimaryKey` as fldFKeyBuyer, `tbl_buyers`.`fldEmail` as fldBuyerEmail, `tbl_buyers`.`fldAddressStreet`, `tbl_buyers`.`fldAddressCity`, `tbl_buyers`.`fldAddressState`, `tbl_buyers`.`fldAddressZip`, `tbl_buyers`.`fldAddressCountry`, `fldPaymentCurrency`, `fldPaymentGross`, `fldPaymentStatus`, `fldReceiverEmail`, `fldTransactionId` 
FROM `tbl_transactions` INNER JOIN `tbl_buyers` 
ON `tbl_transactions`.`fldFKeyBuyer` = `tbl_buyers`.`fldPrimaryKey` 

感谢您的时间！

Answer 1

要使用两个以上的表，只需继续添加JOIN语句来连接外键。适应你的代码中添加一个假想的第三个表tbl_products可能是这样的：

CREATE OR REPLACE VIEW vw_itemsPurchased AS (
    SELECT 
    tbl_buyers.fldPrimaryKey as fldFKeyBuyer, 
    tbl_buyers.fldEmail as fldBuyerEmail, 
    tbl_buyers.fldAddressStreet, 
    tbl_buyers.fldAddressCity, 
    tbl_buyers.fldAddressState, 
    tbl_buyers.fldAddressZip, 
    tbl_buyers.fldAddressCountry, 
    fldPaymentCurrency, fldPaymentGross, 
    fldPaymentStatus, 
    fldReceiverEmail, 
    fldTransactionId, 
    tbl_tproducts.prodid 
FROM 
    tbl_transactions 
    INNER JOIN tbl_buyers ON tbl_transactions.fldFKeyBuyer = tbl_buyers.fldP 
    -- Just add more JOINs like the first one.. 
    JOIN tbl_products ON tbl_products.prodid = tbl_transactions.prodid 

在上述方法中，第一和第二表关联，并且第一和第三表关联。如果必须涉及table1->table2和table2->table3，请列出FROM中的多个表，并将它们与WHERE关联。以下内容仅用于说明，并不具有多少意义，因为您可能不会在产品价格的同一表格中包含客户ID。

SELECT 
    t1.productid, 
    t2.price, 
    t3.custid 
FROM t1, t2, t3 
WHERE 
    -- Relationships are defined here... 
    t1.productid = t2.productid 
    AND t2.custid = t3.custid