Editacia data mysql tabulke cez php

Notice: Undefined index: id_jazdec in update.php on line 13

<?php
$host="mysql.tuke.sk"; // Host name
$username="login"; // Mysql username
$password="psw"; // Mysql password
$db_name="db"; // Database name
$tbl_name="tbl"; // Table name

// Connect to server and select database.
mysql_connect("$host", "$username", "$password")or die("cannot connect");
mysql_select_db("$db_name")or die("cannot select DB");

$sql="SELECT * FROM $tbl_name";
$result=mysql_query($sql);
?>
<table width="600" border="0" cellspacing="1" cellpadding="0">
<tr>
<td>
<table width="600" border="1" cellspacing="0" cellpadding="3">


<tr>
<td align="center"><strong>Meno</strong></td>
<td align="center"><strong>Priezvisko</strong></td>
<td align="center"><strong>Ulica</strong></td>
<td align="center"><strong>Cislo domu</strong></td>
<td align="center"><strong>Mesto</strong></td>
<td align="center"><strong>Startovacie cislo</strong></td>
<td align="center"><strong>Datum</strong></td>
<td align="center"><strong>Editovanie</strong></td>
</tr>
<?php
while($rows=mysql_fetch_array($result)){
?>
<tr>
<td><? echo $rows['meno']; ?></td>
<td><? echo $rows['priezvisko']; ?></td>
<td><? echo $rows['ulica']; ?></td>
<td><? echo $rows['cislo_ulice']; ?></td>
<td><? echo $rows['mesto']; ?></td>
<td><? echo $rows['pocet_osob']; ?></td>
<td><? echo $rows['datum']; ?></td>


<td align="center"><a href="update.php?id=<? echo $rows['id_jazdec']; ?>">Edituj</a></td>
</tr>
<?php
}
?>
</table>
</td>
</tr>
</table>
<?php
mysql_close();
?>

<?php
$host="mysql.tuke.sk"; // Host name
$username="login"; // Mysql username
$password="psw"; // Mysql password
$db_name="db"; // Database name
$tbl_name="tbl"; // Table name

// Connect to server and select database.
mysql_connect("$host", "$username", "$password")or die("cannot connect");
mysql_select_db("$db_name")or die("cannot select DB");

// get value of id that sent from address bar
$id_jazdec=$_GET['id_jazdec'];


// Retrieve data from database
$sql="SELECT * FROM $tbl_name WHERE id_jazdec='$id_jazdec'";
$result=mysql_query($sql);

$rows=mysql_fetch_array($result);
?>
<table width="400" border="0" cellspacing="1" cellpadding="0">
<tr>
<form name="form1" method="post" action="update_ac.php">
<td>
<table width="100%" border="0" cellspacing="1" cellpadding="0">

<tr>
<td align="center">&nbsp;</td>
<td align="center">&nbsp;</td>
<td align="center">&nbsp;</td>
<td align="center">&nbsp;</td>
</tr>
<tr>
<td align="center">&nbsp;</td>
<td align="center"><strong>Meno</strong></td>
<td align="center"><strong>Priezvisko</strong></td>
<td align="center"><strong>Ulica</strong></td>
<td align="center"><strong>Cislo domu</strong></td>
<td align="center"><strong>Mesto</strong></td>
<td align="center"><strong>Startovacie cislo</strong></td>
<td align="center"><strong>Datum</strong></td>
</tr>
<tr>
<td>&nbsp;</td>
<td align="center"><input name="name" type="text" id="meno" value="<? echo $rows['meno']; ?>"></td>
<td align="center"><input name="priezvisko" type="text" id="priezvisko" value="<? echo $rows['priezvisko']; ?>" size="15"></td>
<td><input name="ulica" type="text" id="ulica" value="<? echo $rows['ulica']; ?>" size="15"></td>
<td><input name="cislo_ulice" type="text" id="cislo_ulice" value="<? echo $rows['cislo_ulice']; ?>" size="15"></td>
<td><input name="mesto" type="text" id="mesto" value="<? echo $rows['mesto']; ?>" size="15"></td>
<td><input name="pocet_osob" type="text" id="pocet_osob" value="<? echo $rows['pocet_osob']; ?>" size="15"></td>
<td><input name="datum" type="text" id="datum" value="<? echo $rows['datum']; ?>" size="15"></td>
</tr>
<tr>
<td>&nbsp;</td>
<td><input name="id_jazdec" type="hidden" id="id_jazdec" value="<? echo $rows['id_jazdec']; ?>"></td>
<td align="center"><input type="submit" name="Submit" value="Submit"></td>
<td>&nbsp;</td>
</tr>
</table>
</td>
</form>
</tr>
</table>

<?

// close connection
mysql_close();

?>

<?php
error_reporting(-1);
$host="mysql.tuke.sk"; // Host name
$username="gazi"; // Mysql username
$password="gazi_psw"; // Mysql password
$db_name="gazi"; // Database name
$tbl_name="jazdec"; // Table name

// Connect to server and select database.
mysql_connect("$host", "$username", "$password")or die("cannot connect");
mysql_select_db("$db_name")or die("cannot select DB");
$id_jazdec=$_POST['id_jazdec'];
$meno=$_POST['meno'];
$priezvisko=$_POST['priezvisko'];
$ulica=$_POST['ulica'];
$cislo_ulice=$_POST['cislo_ulice'];
$mesto=$_POST['mesto'];
$pocet_osob=$_POST['pocet_osob'];
$datum=$_POST['datum'];

// update data in mysql database
$sql="UPDATE $tbl_name SET meno='$meno', priezvisko='$priezvisko', ulica='$ulica', cislo_ulice='$cislo_ulice', mesto='$mesto', pocet_osob='$pocet_osob', datum='$datum' WHERE id_jazdec='$id_jazdec'";
$result=mysql_query($sql);

// if successfully updated.
if($result){
echo "Uspesne editovane";
echo "<BR>";
echo "<a href='list_records.php'>Ukaz tabulku</a>";
}

else {
echo "ERROR";
}

?>

$id_jazdec=(isset($_GET['id_jazdec'])) ? $_GET['id_jazdec'] : null;

<a href="update.php?id=<? echo $rows['id_jazdec']; ?>">Edituj</a>

<a href="update.php?id_jazdec=<? echo $rows['id_jazdec']; ?>">Edituj</a>