[Bug] It breaks on using * as selected columns in count()

[antonioribeiro]

Take this select as an example:

select id, (select count(*) from users where users.session_id = sessions.id) as total
from sessions
order by total desc

If you use * instead of my columns we get:

select count(*) from sessions
order by total desc

But there is no total column in that table, so we get an exception. And the same may happen with Group By in some database systems.

[ktunkiewicz]

Merged your pull request. Thanks.

[antonioribeiro]

Thank you!