There are 2 tables:

```
orders:
id   requester_id   supplyer_id  status
1    423            1           reserved
2    500            1           supplied
3    222            2           reserved
...

users
id    username  register_date
1     admin     2012-01-01
2     smith     2013-01-01
...
423   John      2012-10-11
500   Doe       2012-12-11
222   name      2012-10-13 
...

```

I want to join these two tables and get this as a result 

```
id  requester_username   supplier_username  status
1   John                 admin              reserved
2   Doe                  admin              supplied
3   name                 smith              reserved

```

I can actually join these tables using active records like :

```
$this->db->select('orders.*,users.username')
   ->from('orders')
   ->join('users','users.id = orders.requester_id')
   ->get()->result();

```

but I dont know how to get the `supplier username` at the same time.