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i need some help with IF, without else. (Else i use later :) )

So i need a help with this code:

$result = dbquery("SELECT * FROM forum_members WHERE name = '$forum_nick'"); 
if(dbrows($result) != 0) 
 $error .="We didn't find this nick. First sign up to the Forum";

Where is != 0 i need that if don't let register if the user don't register to the forum first. So i nee not !=0 but something like > 1 (doesn't works) or something, i don't know that function..