使用别名从两个不同的表左连接特定列

I have two tables:

我有两张桌子:

toys

item_id int(4) unsigned

item_id int(4)unsigned

item_desc varchar(100)

initial_quantity int(4) unsigned

initial_quantity int(4)unsigned

price decimal(5,2)

and

toy_purchases

item_id int(4) unsigned

item_id int(4)unsigned

customer_name varchar(100)

quantity int(4) unsigned

quantity int(4)unsigned

purchase_date date

Only using aliases, how would I list out only the item description from the toys table, along with only the customer_name and purchase_date (whether or not they exist) from toy_purchases.

仅使用别名,我将如何仅从toy_purchases中列出玩具表中的项目描述以及customer_name和purchase_date(无论它们是否存在)。

I have tried the following:

我尝试过以下方法:

select b.book_name 
from books as b 
left outer join bc.customer_name, bc.purchase_date 
from book_customers as bc on b.bookid=bc.itemid; 

1 个解决方案

#1

That is not the proper syntax for a query. I think you are actually after:

这不是查询的正确语法。我想你实际上是在追求:

SELECT t.item_desc AS Description, 
       tp.customer_name AS Customer, 
       tp.purchase_date AS DatePurchased 
FROM toys t 
LEFT JOIN toy_purchases tp ON t.item_id = tp.item_id