MySQL LEFT JOIN, GROUP BY and ORDER BY not working as required

Question

I have a table

\'products\' => (\'product_id\', \'name\', \'description\') 

and a table

\'product_price\' => (\'pro         


        

Answer 1

It appears that it is impossible to use an ORDER BY on a GROUP BY summarisation. My fundamental logic is flawed. I will need to run the following subquery.

SELECT `p`.*, `pp`.`price` FROM `products` `p` 
LEFT JOIN (
    SELECT `price` FROM `product_price` ORDER BY `date_updated` DESC
) `pp` 
ON `p`.`product_id` = `pp`.`product_id`
GROUP BY `p`.`product_id`;

This will take a performance hit but as it is the same subquery for each row it shouldn't be too bad.