<?php
$users_has_guardservices="
SELECT 
users.name
FROM users
LEFT JOIN plan ON plan.users_id = users.id
LEFT JOIN guardservices ON plan.guardservices_gs_id = guardservices.gs_id
LEFT JOIN events ON guardservices.events_event_id = events.event_id
LEFT JOIN functionnums ON guardservices.functionnums_num_id = functionnums.num_id
LEFT JOIN functions ON functionnums.functions_func_token = functions.func_token
WHERE functions.func_token= '".$row1->func_token."'
AND plan.cell_id=".$f."
AND events.event_id=".$row->event_id."
;
";
$query_users_has_guardservices = mysql_query($users_has_guardservices) or die("Anfrage nicht erfolgreich");
$result_plan = mysql_fetch_row($query_users_has_guardservices);

if(empty($result_plan)){
?>
<table style="width:100%;">
	<tr>
		<td style="width: 20px;" class="entry">
		<?php
	

		?>
		</td>
		<td style="vertical-align:middle; text-align:center;">---</td>
		<td style="width: 20px; text-align: right;" class="entry">
			<a href="insert.php?gs_id=<?=$row1->gs_id?>&user_id=<?=$result_user[2];?>&cell_id=<?= $f; ?>">[ + ]</a>
		</td>
	</tr>
</table>
<?php
}else{
?>
<form action="delete.php" method="post">
	<table style="width:100%;">
	<tr>
		</td>
		<td style="vertical-align:middle; text-align:center;">
			<?php
				echo $result_plan[0];
			?>
		</td>
		<td style="width: 20px; text-align: right;" class="entry">
			<a href="delete.php?gs_id=<?=$row1->gs_id?>&user_id=<?=$result_user[2];?>&cell_id=<?= $f; ?>">[ - ]</a>
		</td>
	</tr>
	</table>
</form>
<?php
}
?>

$.ajax({
  type: "POST",
  url: "dein-script.php",
  data: "var=parameter",
  success: function(result) {
    $("#dein-content-container").html(result);
  }
});

function get_url_param( name )
{
	name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");

	var regexS = "[\\?&]"+name+"=([^&#]*)";
	var regex = new RegExp( regexS );
	var results = regex.exec( window.location.href );

	if ( results == null )
		return "";
	else
		return results[1];
}

<a href="insert.php?gs_id=<?=$row1->gs_id?>&user_id=<?=$result_user[2];?>&cell_id=<?= $f; ?>">[ + ]</a>

//klar: insert.php muss raus, aber wie spreche ich die Funktion an?