I know I am going to get some heat because of it but hey USA is a free country.

declare @user_id int

select @user_id = 2

;with cte

AS

(

select b.id, b.parent_id, b.name as bunit, w.id as wid, w.name as wgrp

from bizunit b

inner join

workgroup_bizunit wb on b.id = wb.bid

inner join

workgroup w on wb.wgid = w.id

inner join

users_workgroup uw on uw.wgid = wb.wgid

where uw.uid = @user_id

union all

select b.id, b.parent_id, b.name as bunit, w.id as wid, w.name as wgrp

from bizunit b

inner join cte

on b.parent_id = cte.id

inner join

workgroup w on cte.wid = w.id

)

select bunit, wgrp

from cte

order by bunit, wgrp