Seeing what percent of users in a database have the code '5'

[tibberous]

I have a table called visitors, and the visitors have different codes. I need to see what percentage have the code 5. Right now I am using:

 

return mysql_num_rows(mysql_query("select code from visitors where code='5'")) / mysql_num_rows(mysql_query("select code from visitors"));

 

But it doesn't seem to work. Does anyone know how else to do this?

 

 

[Barand]

$res = mysql_query ("SELECT SUM(IF(code=5,1,0)) as fives, COUNT(*) as total FROM visitors");

$percent = mysql_result($res,0,'fives') * 100 / mysql_result($res,0,'total');