Update rows with ID in array (and more)

[bayswater]

Hi,

Ok, so I'm making a registration form system, where I can create new registration forms for the users to pick a date etc.

In my form I can add and remove text fields via Javascript - to add additional dates etc. so I don't know if I'll be submitting 3 fields or 15.

The could look like this:

<input type="hidden" name="session_id[]" value="<?php echo $session_id; ?>">
<input type="text" name="picked_date[]">
<input type="text" name="picked_room[]">

They are put in a big array:
De bliver smidt i et stort array:

    $n=0;
    foreach ($session_id as $_session_id) {
        $bigar[$n][1] = $_session_id;
        $n++;
        }
        $n=0;
    foreach ($picked_date as $_picked_date) {
        $bigar[$n][2] = $_picked_date;
        $n++;
        }
        $n=0;
    foreach ($picked_room as $_picked_room) {
        $bigar[$n][3] = $_picked_room;
        $n++;
        }
        $n=0;

which is then updated in the database using:
foreach ($bigar as $part)

{
mysql_query("UPDATE...
}

Right - so far so good. The updating works fine with existing fields, but if I remove some of the fields (via JS) it obviously only updates the remaining in the array. The left out will be ignored. On the same note I would like to add fields as well, so - the bottom line - I want to:

• UPDATE rows, where the ID is in the array
• DELETE existing rows, WHERE the ID is NOT in the array
• CREATE new rows for the new fields in the array (not having an ID)

How can this be achieved? Hope someone can help...

[doobster]

I would do the following:

1. On submit, delete all records for that user.
2. Loop through and insert all records.

This will always ensure you only have the correct records. The only downside to this approach is your primary key being auto increment will grow quickly, but it shouldn't be that big of a deal.