Oops Lover

<?php
@session_start();
@ob_start();
//class created
class user_handler{
//function created for insert into table
function insert_data($userdata,$table){
$user_field = implode(",",array_keys($userdata));
$user_value = implode("','",array_values($userdata));
echo $insert = "INSERT INTO $table($user_field) VALUES('$user_value')";
$insert_que = mysql_query($insert) or die(mysql_error());
if($insert_que){
header("location:./enter_job_detail.php");
}
else{
header("location:./enter_job_detail.php");
}
}
function login($username,$password,$table){
$user_name = "SELECT * FROM $table WHERE username = '$username' AND password = '$password'";
$login_sql = mysql_query($user_name) or die(mysql_error());
$check = mysql_num_rows($login_sql);
if($check>0){
$fetch_login = mysql_fetch_array($login_sql);
$_SESSION['login'] = $fetch_login['id'];
header("location:./home.php");
//echo"enter";
}
else{
header("location:./index.php");
//echo"not enter";
}
}
function fetch_data($table){
$select_data  = "SELECT * FROM $table";
$fetch_que    = mysql_query($select_data);
//$fetch_data   = mysql_fetch_array($fetch_que);
$fetch_data   = array();
while($row    = mysql_fetch_assoc($fetch_que)){
$fetch_data[] = $row;
}
return $fetch_data;
}
function update_data($userdata,$table,$id){

$update_detail = "UPDATE $table SET ";
$flag = 0;
foreach($userdata as $key=>$value){
if($flag){
$update_detail .= ",";
}
$update_detail .= $key."='".$value."'";
$flag = 1;
}
$update_detail .=" WHERE id = '$id'";
$sql_update = mysql_query($update_detail);
}
}