mysql + php retrieve leaf children with path

I have a table that like this.

+-----------+-----------+-----------+-----------+-----------+-----------+
|id         | parent_id | name      | order     | status    | date_add  |
+-----------+-----------+-----------+-----------+-----------+-----------+
|1          | 0         | shoes     | 1         | 1         | 2011-04-02|
+-----------+-----------+-----------+-----------+-----------+-----------+
|2          | 1         | male      | 2         | 1         | 2011-04-02|
+-----------+-----------+-----------+-----------+-----------+-----------+
|3          | 1         | female    | 3         | 1         | 2011-04-02|
+-----------+-----------+-----------+-----------+-----------+-----------+
|4          | 3         | red shoes | 4         | 1         | 2011-04-02|
+-----------+-----------+-----------+-----------+-----------+-----------+

I want to select only the leaf children, with their path.

I want to come to the result as fol开发者_开发技巧lows:

+------+-------------------------------------+
| 2    | shoes/male                          |
+------+-------------------------------------+
| 4    | shoes/female/red shoes              |
+------+-------------------------------------+

if this does not only sql can also be php + sql

Please help me.

Very simple solution to print out id and path to all last child nodes using PHP as I am not aware of a way of doing this within MySQL. Hope this helps!

function getChildren($parent= "", $x = 0) {
   $sql = "SELECT id, name FROM recurr WHERE parentId = $x";
   $rs = mysql_query($sql);
   //echo "Name: $parent has ". mysql_num_rows($rs)." children<br/>";
   while ($obj = mysql_fetch_object($rs)) {
      if (hasChildren($obj->id)) {
         getChildren($parent."/".$obj->name, $obj->id);
      } else {
         echo $obj->id .", ".$parent."/".$obj->name."<br/>";
      }
   }
}

function hasChildren($x) {
   $sql = "SELECT * FROM recurr WHERE parentId = $x";
   $rs = mysql_query($sql);
   if (mysql_num_rows($rs) > 0) {
      return true;
   } else {
      return false;
   }
}

To run just call:

getChildren();

I highly recommend implementing nested set model for hierarchical MySQL data. Here is the link for more info: http://mikehillyer.com/articles/managing-hierarchical-data-in-mysql/. In the link, you will also find the answer to your question (under "The Adjacency List Model", "Finding all the Leaf Nodes" section)