Question

I have two tables and they are as follows:

USERS
ORDERS

I want select all users who have at least 1 order or more in the ORDERS table. I know there is an inline query for this in MySQL, but right now I have to select all users and then make another query seeing if each user has an order – all this using a PHP loop.

What I am doing now is not ethically correct, so I basically just want to select all users who have been referenced in the ORDERS table in ONE MySQL query.

Answer 1

This is a query you should be using

select distinct u.* from users u
inner join orders o on o.user_id = u.id;

Note the distinct and u.*. This query will not select fields from orders and it will not select the same user twice (if one has more than one order).

Demo: http://sqlfiddle.com/#!2/6ebcc/3