Using php recursion to realize the detail of infinite classification formatting array

We're going to do an infinite class of goods
First, the database field is:
id -- Commodity primary key id
fid -- The father of the product
name -- Product name
The final output is in the form of an array

<PRE class=php name="code"><PRE class=php name="code">array(
 0=>array(
  'id'=>1,
  'fid'=>0,
  'name'=>' French goods '
  'child'=>array(
   0=>array( 
    'id'=>12,
    'fid'=>1,
    'name'=>' perfume '
    'child'=>array(
     0=>array(
      'id'=>34,
      'fid'=>12,
      'name'=>' The female perfume '
     )
    )
   ),
   1=>array(
    'id'=>13,
    'fid'=>1,
    'name'=>' The notebook '
    'child'=>NUll
   )
  )
 ),
 1=>array(),    // Again, I'm not going to repeat it   It doesn't make sense 
 2=>array()
)</PRE><BR>
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<PRE></PRE>
php Code: 
<P></P>
<P></P>
<PRE class=php name="code"><?php
// I used the database mysql PDO   But the whole idea is again 1 The sample of 
$conn=mysql_connect('localhost','root','123');
if(mysql_errno()){
 printf(' The connection fails '.mysql_error());
}
mysql_select_db('edeng');
mysql_set_charset('utf8');
/*
 * Recursive function 
 *@param id  In order to query fid=$id All subclasses of    There will be $id The default value of is set to 0   Because I put the topmost category in the database fid Set to 0
 */
function get_array($id=0){
 $sql="select id,fid,cname from e_cat where fid= $id";
 $result=mysql_query($sql);
 $arr=array();
 if($result && mysql_affected_rows()){
  while($rows=mysql_fetch_assoc($result)){

   $rows['child']=get_array($rows['id']);
   $arr[] = $rows;
  }
  return $arr;
 }
} 
echo '<pre>';
$result = get_array();
print_r($result);
</PRE><BR>
<BR>
<P></P>
<P>&nbsp;</P>
<P> The function first queries all of them fid for 0 The class of </P>
<P> through while Loop back to find fid For the current class id A subclass of </P>
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</P>
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</P>
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