Have you tried using SQL sub-selects? I can never remember the syntax
without looking it up but it's something like:
SELECT signup.code, signup.count, visit.count FROM (SELECT count(*),
c.code FROM signups s......) AS signup JOIN (SELECT ....) AS visit ON
visit.code = signup.code;
You can do this via either model, I don't think it cares what attributes
are returned!
Hope that helps!
Andrew