[undefined-index] Forum Topics

Hi, so im trying to insert data but i get: > Notice: Undefined index: events html part: <form method="post" action="seating.php> <div class="drop"> <label>Event : <label/> <select name="events" id="dd-events" onchange="getguests(this.value)"> <option value="" disabled selected >Event</option> <?php foreach($retrieve as $r): ?> <option value="<?=$r['event_id']?>"><?=$r['event_name']?></option> <?php endforeach ?> </select> </div> <input type="hidden" name="table_name[]" value='+tablename+'><span …