Sql tablodan iki alanı seçip aynı tabloya join işlemi yapma

I have two tables:

users(userid, username)

and

cases(cid,assign_to,received_by)

I want to join assign_to and received_by with user_id and produce username.

How do I join these table and how I produce username to assign_to and received_by?

These two fields assign_to and received_by are stored different userid.

> eg assign_to received_by
> 1 3
> 2 4

I want to produce username in these fields.

Kaynak:http://stackoverflow.com/questions/1695542/sql-query-two-field-from-one-table-join-one-field-from-a-table