How to replace the uploaded file in php edit page?

 if(array_key_exists('insert',$_POST))

 {  

            include("config.php");

            $frmt_code=$_POST[frmt_code];

            $frmt_des=$_POST[frmt_des];

            $version_no=$_POST[version_no];

            $version_date=$_POST[version_date]; 

            $Dept_Name=$_POST[Dept_Name]; 

            $pdf_file=$_POST[pdf_file]; 

            $sql="INSERT INTO format_master (frmt_code,frmt_des,version_no,version_date,Dept_Name,pdf_file)VALUES('$frmt_code','$frmt_des','$version_no','$version_date','$Dept_Name','".$_FILES['pdf_file']['name']."')";

  $path= "pdf/".$HTTP_POST_FILES['pdf_file']['name'];

  if($pdf_file !=none)

  {

  if(copy($HTTP_POST_FILES['pdf_file']['tmp_name'], $path))

  {

  }

  else

  {

  echo "Error";

  }

  }

  $result=mysql_query($sql) or die(mysql_error());

            if ($result)

            {

                header('Location:    http://localhost/EMP/frmtview.php');

                exit;

                }

  }

  ?>

 

   

   

                    

Format Code
Format Description
Version Number
Version Date	:
Deportment  Name	:	--- Select ---                    include("config.php");             $select="hoshin";             if (isset ($select)&&$select!=""){             $select=$_POST ['Dept_Name'];         }         ?>                     $list=mysql_query("select * from dept_master order by Dept_Name asc");         while($row_list=mysql_fetch_assoc($list)){             ?>                 >                                                                              }             ?>
File Name	:

   

   

   

   

   

   

Using this code file uploaded to the folder & the file name has stored in mysql database in row "pdf_file". I need to replace the file in edit page and want the path in view page. Is anybody can help me?