内部连接的 SQL where 子句

Posted 2023-02-24

【中文标题】内部连接的 SQL where 子句

【英文标题】：SQL where clause on inner joins

【发布时间】：2016-08-17 08:45:24

【问题描述】：

我正在使用 pgadminIII (postgreSQL)

我有以下表格： 书， 出版商， 订单行， ShopOrder。

使用以下 SQL：

SELECT 
    Book.BookID AS "Book ID"
    ,Book.Title AS "Book title"
    ,SUM(OrderLine.quantity) AS "Number Ordered"
    ,ShopOrder.OrderDate AS "Order Date"
FROM (((Book

INNER JOIN OrderLine
ON Book.BookID = OrderLine.BookID)

INNER JOIN Publisher
ON Book.PublisherID = Publisher.PublisherID )


INNER JOIN ShopOrder
ON OrderLine.ShopOrderID = ShopOrder.ShopOrderID)

GROUP BY ShopOrder.OrderDate, Name, Book.BookID

.

我想将它与 (WHERE Publisher.Name = "Smith Smitheson") 一起使用

我不知道把它放在哪里，或者如果我做得对，请帮忙？

【参考方案1】：

...
INNER JOIN Publisher ON Book.PublisherID = Publisher.PublisherID AND Publisher.Name = 'Smith Smitheson' )
...

或

SELECT Book.BookID AS "Book ID" ,Book.Title AS "Book title"   
,SUM(OrderLine.quantity) AS "Number Ordered" ,ShopOrder.OrderDate AS  
"Order Date" FROM Book
INNER JOIN OrderLine ON Book.BookID = OrderLine.BookID
INNER JOIN Publisher ON Book.PublisherID = Publisher.PublisherID 
INNER JOIN ShopOrder ON OrderLine.ShopOrderID = ShopOrder.ShopOrderID
WHERE Publisher.Name = 'Smith Smitheson'
GROUP BY ShopOrder.OrderDate, Name, Book.BookID