;WITH WGBizTree (bid, bname, wgid, wgname) AS
    -- anchor part
    (SELECT wb.bid, b.name AS bname, wb.wgid, w.name AS wgname
      FROM users_workgroup uw
        INNER JOIN workgroup_bizunit wb ON uw.wgid = wb.wgid
        INNER JOIN bizunit b ON wb.bid = b.id
        INNER JOIN workgroup w ON wb.wgid = w.id
      WHERE uw.uid = @UserID
    UNION ALL
    -- recursive part
    SELECT b.id, b.name AS bname, bt.wgid, w.name AS wgname
      FROM WGBizTree bt
        INNER JOIN bizunit b ON bt.bid = b.parent_id
        INNER JOIN workgroup w ON bt.wgid = w.id)
SELECT bname, wgname
  FROM WGBizTree
  ORDER BY bname, wgname