代码的这一特定部分无法正常工作

my code :

$Query = mysql_query("INSERT INTO employee SET firstname='".$firstname."',lastname='".$lastname."',gender='".$gender."',
        email='".$email."',mobile='".$mobile."',empid='".$empid."',address='".$address."',dob='".$dob."',photo='".$photo."',
        password='".$password."',sales_manager='".$sales_manager."',designation='".$designation."',reg_date='".$reg_date."',
        res_manager='".$res_manager."',lead_limit='".$lead_limit."',lead_cycle='".$lead_cycle."',qualification='".$qualification."',
        experience='".$experience."',target='".$target."',c_delete='N',status='Active'");
    }
    else
    {
        $Query = mysql_query("INSERT INTO employee SET firstname='".$firstname."',lastname='".$lastname."',gender='".$gender."',
        email='".$email."',mobile='".$mobile."',empid='".$empid."',address='".$address."',dob='".$dob."',
        password='".$password."',sales_manager='".$sales_manager."',designation='".$designation."',reg_date='".$reg_date."',
        res_manager='".$res_manager."',lead_limit='".$lead_limit."',lead_cycle='".$lead_cycle."',qualification='".$qualification."',
        experience='".$experience."',target='".$target."',c_delete='N',status='Active'");
}
//this is for photo..

//this is used for chatting...usr_roll='".$usr_roll."'
$qch = mysql_query('SELECT * FROM stud_data order by desc');
$qch_rs=mysql_fetch_array($qch);
if(isset($qch_rs['id']))
{

    $usr_roll=$qch_rs['usr_roll']+1;
     echo $usr_roll;
    $Query = mysql_query("INSERT INTO stud_data SET usr_name='".$firstname."',
    usr_roll='".$usr_roll."',usr_unique_id='".$empid."'");
    echo "HELLO";
     echo $Query;
}
//this is used for chatting...

if($Query)
{

    $_SESSION[MESSAGE_TEXT]="Employee Added Successfully ...";
    $_SESSION[MESSAGE_TYPE] = "msgsuccess";
    header("location:index.php?p=".$_REQUEST['p']."");
    exit();
}
else
{

    $_SESSION[MESSAGE_TEXT]="Record did not Insert...";
    $_SESSION[MESSAGE_TYPE] = "msgerror";
    header("location:index.php?p=".$_REQUEST['p']."");
    exit();
}
}

your query is missing order by id

$qch = mysql_query('SELECT * FROM stud_data order by desc');

use

$qch = mysql_query('SELECT * FROM stud_data order by id desc');

As per your given code you should use the variables to take the values and then make a insert statement for example you are using 2 insert statement instead of that you can take the values in variable and then insert like :

$firstname = $_POST['first_name];

etc. by this way you don't need to create 2 insert satement.

Apart from that

$qch = mysql_query('SELECT * FROM stud_data order by desc');

whenever you use order by clause this always take a column name in it so use id or name whatever you want to order by.

Hope this helps.

Thanks Randheer