So I assume that you have a field call access_level
the query
//68 is the user id to be banned
int user_id = 68; //to be banned
String query = "update table_name set access_level = 2 where
user_id = "+user_id;
String query2 = "select * from table_name where access_level =
2";
Haven't touched java for a while but this should work.
Cheers
Gary