Question

I have a table where I keep all my templates:

templates

• template_id
• template_name
• template_price

These templates can be purchased by a registered user and then are inserted in the payments table:

payments

• payment_id
• template_id
• user_id

Is there a way to join these two tables and get not just a list of templates that have been purchased by a certain user, but all the templates? And then figure out from there which ones have already been purchased?

I used this SELECT, but only the ones that the user bought showed up. I would like to have all the rows from templates, but empty in case the user_id doesn’t match.

SELECT *
FROM templates
LEFT JOIN payments
ON templates.template_id = payments.template_id
WHERE user_id = 2
GROUP BY templates.template_id

Answer 1

Using a subselect this would be

SELECT t.*, p.payment_id
FROM templates t
LEFT JOIN (
    SELECT * FROM payments WHERE user_id=2
) p ON t.template_id = p.template_id

This shows you all the templates and the payment_id, if there is one for that user.