Can anyone help me figure out the meaning of this php error message? [duplicate]

Answer 1

if(isset($_POST['user_name'], $_POST['password'], $_POST['user_type'])){
    $data = mysql_query("SELECT * from users 
             where user_name = '".mysql_real_escape_string($_POST['user_name'])."' and 
                   password  = '".mysql_real_escape_string($_POST['password'])."' and 
                   user_type = '".mysql_real_escape_string($_POST['user_type'])."' ");

    if(mysql_numrows($data) == 1) {
       $info = mysql_fetch_array($data);
       echo("Success!!");
    } else {
       echo("BIG FRIGGIN FAILURE!!");
    }
}
else{
   echo "Required Data Missing";
}

mysql_close($con);