query according to isset($variable)

[CarpeDiem]

hi everybody,
I use a simple data form to take input from users.
users can modify data on mysql database via this form.
so, it must be sent query to database (updata table set newvalue=something where unique_id=$unique_id)
something like that... but here; newvalue must be set according to users input. if user did not input thatVariable, code must not include (....set thatVariable=something...) , that is why only inputted data must be included in query. for example I have 9 variables on my form.. as a result of users input I want to send query into mysql database include only inputted variables Set Command. others datas wll keep as their old values.

any helps are appreciated..
regards.
//metin..

[steps]

I think you can't do this with isset(), because if you have a form submitted (via POST I hope), the variables are set even if the hasn't filled out the inputfields.

You need to walk through $_POST and check the value for each key:

reset($_POST);
while (list ($key, $val) = each ($_POST)) {
    if($val != '')  {

    (add values to query) ....
   }
}