How can I get a result set which contains a column with the manager's name, like this:

```
+----+---------+-----------+
| id | empname |managername|
+----+---------+-----------+
|  1 | sandeep |   NULL    |        
|  2 | xyz     |   sandeep |
|  3 | abc     |   xyz     |         
+----+---------+-----------+

```