Facebook SDK FQL: Getting profile URL?

Question

I am using fql from facebook and querying user table to get profile_url

string facebook_info = Convert.ToString(FacebookAppExtensions.Query(app, "**SELECT 
                       profile_url from user where uid=" + facebook_ID**));
facebook_info = facebook_info.Substring(17);
char[] charsToTrim1 = { '}', ']', ' ', '"' };
facebook_info = facebook_info.TrimEnd(charsToTrim1);

The problem is that for some users the URL works while for other users, facebook says "UNKNOWN" page, is this a bug?

Thanks Behrouz

Answer 1

no need to query: http://www.facebook.com/profile.php?id=UID

Answer 2

I think as all data you can fetch this is controlled by the user too. If user doesn't let you fetch data about him, then you don't get that data via FQL.