I have two tables:
toys
item_id int(4) unsigned
item_desc varchar(100)
initial_quantity int(4) unsigned
price decimal(5,2)
and
toy_purchases
item_id int(4) unsigned
customer_name varchar(100)
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.
I have tried the following:
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;
That is not the proper syntax for a query. I think you are actually after:
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
To left join table1 with only specific columns from table2 using an alias we can do this:
SELECT
A.*, B.aThingIWant1, B.aThingIWant2
FROM table1 A
LEFT JOIN table2 B
ON A.id = B.application_id
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