ohhh, thats a bit ahead of my sql-knowledge.
don't know if this is even possible
i just know a (real) bad but working way, but it is very very hardcoded:
PHP Code:
$var=$DB_site->query_first("SELECT SUM(IF(field5='1',1,0) as forum1, SUM(IF(field5='2',1,0) as forum2 FROM userfields");
so you can use $var[forum1], $var[forum2] and so on (if you make a longer query

) and can compare all these....
i know, it's veryy bad, but i don't know another way ....