How to SQL query posts IDs by categories AND authors?

Question

I am making a custom WP_Query and I need to come up with a SQL query that gets the posts IDs from X categories and Y authors. Then merge those IDs and put them in an array.

I only need to figure out the SQL query. Everything else, I got it.

I have looked everywhere for this but no one has been able to help me. Please help me out!!

Answer 1

Not the best solution :P but this could help you:

select 
    distinct(p.ID)
from
    wp_posts p,
    wp_term_relationships r,
    wp_term_taxonomy tt,
    wp_terms t
WHERE
    p.post_author in (1, 2, 3)
        and r.object_id = p.ID
        and tt.term_taxonomy_id = r.term_taxonomy_id
        and tt.taxonomy = 'category'
        and tt.term_id = t.term_id
        and t.term_id in (1, 2, 3);