values from multiple instances of the same button

[drod]

Hi,
I'm trying to use the same input button in a loop and determine which one was selected. For example,

while (<select row from database>){
thisId = $row["id"];
// display remaining row details

// add an input button to update this record
<input type=image name=update src=buttonimage>

}

I want to be able to detect the value of "thisId" when one of the records is updated.
Can anyone explain the best way to do this?
Thanks