Get Parent Id name in same table

Get same table id to parentid name


SQL : 

$sql=$this->db->query("SELECT a.id, a.name, a.sorder, a.isactive, b.name AS 'ParentName' FROM category AS a LEFT JOIN category AS b on a.parentid = b.id  where a.parentid!='0' order by a.parentid asc ");

return $sql->result();