<?php
$username="user";
$password="pass";
$database="DB";

mysql_connect(localhost,$username,$password);
mysql_select_db($database) or die( "Unable to select database");
$query="SELECT id, firstname, lastname, town, age, date FROM signin GROUP BY firstname, lastname WHERE Date =< now() - INTERVAL 30 DAY";
$result=mysql_query($query);

$num=mysql_numrows($result);

mysql_close();
?>
<table border="1" cellspacing="2" cellpadding="2">
<tr>
<td>ID</font></td>
<td>FirstName</td>
<td>LastName</td>
<td>Town</td>
<td>Age</td>
<td>Date</td>
</tr>

<?php
$i=0;
while ($i < $num) {

$f1=mysql_result($result,$i,"firstname");
$f2=mysql_result($result,$i,"lastname");
$f3=mysql_result($result,$i,"town");
$f4=mysql_result($result,$i,"age");
$f5=mysql_result($result,$i,"date");
?>
<?php if (lessThanOneMonthFromNow($f5)){ ?>
<tr>
<td><a href="<?php echo "submit.php?FName=".$f1."&LName=".$f2."&Town=".$f3."&Age=".$f4 ?>">Signin</a></td>
<td><?php echo $f1; ?></td>
<td><?php echo $f2; ?></td>
<td><?php echo $f3; ?></td>
<td><?php echo $f4; ?></td>
<td><?php echo $f5; ?></td>
</tr>
<?php
}
$i++;
}
function lessThanOneMonthFromNow($enteredDate){
   return $enteredDate < date("Ymd", mktime(0, 0, 0, date("m")-1, date("d"), date("y")));
}
?>