Simple and easy-to-use counter (database)_PHP tutorial

Usage
include("counter.php");
Counter(__FILE__);//Increase a count for the file
if($PHP_SELF=="/index.php")
{
$count=Counter("INDEX_COUNT");//Add a count to the home page
}
else
{
$count=Counter("INDEX_COUNT","" ,0);//Get homepage count
}
echo "You are the $count visitor";
?>
--------counter.php-- ---------
if(!isset($PHP_INCLUDE_COUNTER_PHP))
{$PHP_INCLUDE_COUNTER_PHP=__FILE;

$counter_error_state=0;
$counter_error_msg="";
function Counter($file,$query="",$add=1)
{
$db_name="database";
$db_user="username";
$db_pass="password";
$db_table="counter";

if(empty($file))
$counter_error_state=-10 0;
$counter_error_msg="The first parameter is missing or empty";
                          return -100;                                                  (empty($ db_user)||!$db_user||$db_user=="")$res=@mysql_connect("localhost");
     else $res=@mysql_connect("localhost",$db_user,$db_pass); >                                                                                                                                   turn -10;
}
if(!@ mysql_select_db($db_name))
                                                                                                                 return -11;
                                                                                        
                                                                                                                                                                                  l_query("CREATE TABLE ".$db_table." (id INTEGER AUTO_INCREMENT,PRIMARY KEY (id),file VARCHAR(255),query VARCHAR(255),time VARCHAR(255),count INT)"))
                                $counter_error_states=-20;
$counter_error_msg ="Cannot create data table";
                                                                                                                                                            
                  @mysql_free_result($db_res);
                                         "" AND query="".$query. """;

if(!$db_res=@mysql_query($str))
> >                 return -30;
                                                 num>1)
                                                                                                             "An unexpected error occurred = wrong number of data rows";
                                                                                                                                 str="INSERT ";
$strWhere=" ";
if($num==1)
{
$row=@mysql_fetch_array($db_res);
                           @mysql_free_result($db_res); count"];
$id=$row["id"];
$str="UPDATE ";
$strWhere=" WHERE id= $id";
                                  
                if($add<1)return $count;
                $count+=$add;
                $str.=$db_table." SET file="".$file."",query="".$query."",time="".date("Y;n;d;G;i;s")."",count=".$count.$strWhere;
                $db_res=@mysql_query($str);
                if(!$db_res)
                {
                        $counter_error_states=-50;
                        $counter_error_msg="不能添加或更新记录";
                        return -50;
                }
                return $count;
        }
}

}
?>