使用SQL将结果限制为不同的列

Question

I am attempting to get a list of items along with the order information for each item. An order always has at least 1 item associated with it. I want to limit this list to all of the items from 10 orders . As my query stands below, it gets 10 items . What is the best way to LIMIT this to 10 orders, while grabbing all of the items associated with these orders (be it 10 rows or 200 rows)?

SELECT o.*, i.*
FROM orders o, items i
WHERE i.order_id = o.id
LIMIT 0, 10

Much thanks!

Answer 1

Try using a subselect where you limit the orders first. In the outer select you then can fetch all items to these 10 orders.

SELECT o.*, i.*
FROM items i, (SELECT * FROM orders LIMIT 0, 10) o
WHERE i.order_id = o.id

Answer 2

SELECT oo.*, i.*
FROM (
  SELECT *
  FROM orders o
  LIMIT 10
  ) oo , items i
WHERE i.order_id = oo.id

Answer 3

I don't know mysql but to take a guess

SELECT o.*, i.*
FROM orders o, items i
WHERE i.order_id = o.id and 
o.id in (select o.id from orders o limit 0, 10)

Answer 4

Something like this should work:

SELECT o.*, i.*
FROM items i INNER JOIN orders o ON o.id = i.order_id
WHERE o.order_id IN (
  SELECT o.id
  FROM orders
  LIMIT 0, 10
)

Answer 5

SELECT orders1.*, items.*
FROM
(select * from orders 
LIMIT 10) AS orders1
LEFT JOIN items ON orders1.id = items.order_id;