Handle POST from dynamically added form fields

POST_dynamic_fields.php

<div class="button insert">Добавить поле</div>
<form class="ui-filterable" method="POST">
	<?
	$sum=4;
	for ($count=0; $count <$sum ; $count++)
	{
		?>
		<input type="text" class="input text" name="preset[]" placeholder="text" value="preset text <?=$count?>"/>
		<?}?>
		<input class="button submit" type="submit">
		<?
		if($_SERVER['REQUEST_METHOD']=='POST')
		{
			if($_POST['preset'])
			{
				foreach ($_POST['preset'] as $preset => $value)
				{
					echo "UPDATE db SET text='{$value}' WHERE id=".$preset;
					echo "<br/>";
				}
			}
			echo "<br/>";
			if($_POST['text'])
			{
	// var_dump($_POST['text']);
				foreach ($_POST['text'] as $text => $value)
				{
					echo "INSERT INTO db (text) VALUES ('{$value}')";
					echo "<br/>";
	// echo "text: ".$text."<br/>";
	// echo "value: ".$value."<br/>";
				}
			}
			else
			{
				echo "no post text";
			}
		}
		else
		{
			echo "no post";
		}
		?>
	</form>
	<script type="text/javascript">
		var i=0;
		function createTable (argument)
		{
			$('.submit').before('<input type="text" name="text[]" placeholder="text" value="test text '+i+'" class="input text"/>')
			i++;
		}
		$(document).ready(function()
		{
			$('.button.insert').click(function()
			{
				createTable();
			});
		});
	</script>