wordpress - get link attribute id using jquery -

i working in wordpress.i want data-id value when click on link.

my code this:

<?php      $query3 = "select t.* wp_terms t                join wp_term_taxonomy tt on tt.term_id = t.term_id               tt.parent = ".$res2->term_id;               $result3 = $wpdb->get_results($query3);       foreach($result3 $res3)     { ?>         <li>             <a href="##" class="sub_cat_name" data-id= "<?php echo $res3->term_id; ?>"><strong><?php echo $res3->name; ?></strong></a>         </li> <?php      } ?> 

and jquery code is:

<script>  $(document).ready(function(){     $(".sub_cat_name").click(function(){         var cat_id = $(".sub_cat_name").attr("data-id");         alert(cat_id);         });     }); </script>  

when click on different link alert fist term_id.so code should have write different id while click on different link.

you can data-id value using 'data' like.

$(".sub_cat_name").click(function(){     var cat_id = $(this).data("id");     alert(cat_id);     });