<a href='http://somesupersite.com' id='246' class='track'>My Link</a>

$(document).ready(function(){
$('a.track').click(function() {
$.post('http://mysupersite.com/sys/tracker.php', {id:this.id});
});
});

$id = $_POST['id'];
$con = mysqli_connect($mysqlHost, $mysqlUser, $mysqlPassword, $mysqlDatabase);
mysqli_query($con, "UPDATE table SET clicks = clicks + 1 WHERE id = $id");