连接表中的mySQL ORDER BY

Question

Ok, so i have the following schema and query which is very slow (when using real data) because of the ORDER BY:

http://sqlfiddle.com/#!2/5e7bb/10

As per mysql man : "You are joining many tables, and the columns in the ORDER BY are not all from the first nonconstant table that is used to retrieve rows. (This is the first table in the EXPLAIN output that does not have a const join type.) "

but i still need to sort by that column. How would i need to do this ?

Answer 1

UPDATE: since the fiddle was updated :

SELECT
    cpa.product_id, 
    cp.product_internal_ref, 
    cp.product_name, 
    cpa.product_sale_price, 
    cpa.is_product_service, 
    cpa.product_service_price
FROM 
    catalog_products_attributes cpa
JOIN
    catalog_products cp ON cp.product_id = cpa.product_id 
WHERE
    cpa.product_id IN (
        SELECT
            product_id
        FROM 
            catalog_products_categories
        WHERE
            category_id = 41 
    )
ORDER BY 
    cpa.product_service_price DESC