MySQL GROUP BY two columns

Question

I\'m trying to group by multiple columns here - one on each table.
It\'s a scenario where I want to find the top portfolio value for each client by adding their current

Answer 1

Using Concat on the group by will work

SELECT clients.id, clients.name, portfolios.id, SUM ( portfolios.portfolio + portfolios.cash ) AS total
FROM clients, portfolios
WHERE clients.id = portfolios.client_id
GROUP BY CONCAT(portfolios.id, "-", clients.id)
ORDER BY total DESC
LIMIT 30