jQuery无法从Ajax运行

Guys i have a big problem, I have this jquery (I think) code, this code doesn't works from the ajax, and I don't know why, maybe someone can help me.

function showname(id){
    $.ajax({
       url:'tooltip.php',
       data:{id:id},
       async: false,
       success:function(response)
       {
          // use response for tooltip
          alert(response);
       }
    });
});
}

I put an alert on the php code, and the php code works when I call from url (like http://mysite.com/tooltip.php?id=LNFC without " ' ") that code must return the result of the query done on php code.

Php code

<?php 
$q="SELECT complete_name from mytable where id='".$_REQUEST['id']."'" or die(mysql_error()); 
$result=mysql_query($q,$conection); 
$row=mysql_fetch_assoc($result); 
echo $row['complete_name']; 
?>

Thanks.

Try this instead:

function showname(id){
    $.ajax({
       type:'POST',
       url:'tooltip.php',
       data:{id:id},
       success:function(response) {
          // use response for tooltip
          alert(response);
       },
       error:function(response) {
           alert(response.errorThrown); 
       }
    });
}