Question

I have 3 tables: posts, tags, *posts_tags* . I want to list posts, and all tags associated with them, but to limit the results.

This is what I do now:

SELECT 
    p.*,
    t.*
FROM 
    (
        SELECT * FROM  posts LIMIT 0, 10
    ) as p
    LEFT JOIN
        posts_tags as pt
        ON pt.post_id = p.post_id
    LEFT JOIN
        tags as t
        ON t.tag_id = pt.tag_id

It is working fine, but it seems to be a little bit slow..

Is there a better/faster way of doing this? Can I apply LIMIT somewhere else for better results?

EDIT: I want to limit posts, and not results. A post can have many tags.

Answer 1

Have you tried moving the limiting subquery to the where clause instead:

SELECT 
    p.*,
    t.*
FROM 
    posts as p
LEFT JOIN
    posts_tags as pt
    ON pt.post_id = p.post_id
LEFT JOIN
    tags as t
    ON t.tag_id = pt.tag_id
WHERE
    p.post_id in (select post_id from post limit 0,10)