[Taipan]

Originally Posted by Old Pedant

Shoot, then you are making it *WAY* too hard!

SELECT 
    id
FROM 
    products 
    WHERE category_id = 3
    OR product_id IN ( 
        SELECT product_id 
        FROM products_extra_categories 
        WHERE category_id = 3 )
ORDER BY id

Thank you so much, so easy in hind sight