WITH tbl AS (SELECT /*+ MATERIALIZE */ DISTINCT sfd.s_special, (CASE
                 WHEN sfd.s_cpecial IS NULL THEN
                  cp.idz
                 ELSE
                  sfd.s_cpecial
               END) s_cpecial, /*ts.s_vidobyh,*/ d.s_vdiscip
          FROM spec_from_de           sfd,
               iss_spr.cpecial        cp,
               isa_test.discip        d,
               isa_test.SECTION       sec
         WHERE cp.s_special = sfd.s_special
           AND sfd.s_section = sec.idz
           AND sec.s_vdiscip = d.idz
           AND sfd.active = 1)

SELECT DISTINCT op.s_special,
       op.s_cpecial,
       ud.s_fur s_vdiscip,
       (SELECT DISTINCT tbl.s_vdiscip
          FROM tbl

           WHERE tbl.s_special = op.s_special
           AND tbl.s_cpecial = op.s_cpecial
           AND tbl.s_vdiscip=ud.s_fur) AS tstd1

  FROM isu_umu.varplan@asunt1_u.rgups.edu.mps vp
 INNER JOIN isu_umu.plan@asunt1_u.rgups.edu.mps p
    ON vp.s_plan = p.idz
   AND p.s_podsist = 5
 INNER JOIN isu_umu.obrprog@asunt1_u.rgups.edu.mps op
    ON p.s_obrprog = op.idz
 INNER JOIN isu_umu.mestode@asunt1_u.rgups.edu.mps md
    ON p.s_mestode = md.idz
   AND md.s_fil = 117
 INNER JOIN isu_umu.prot@asunt1_u.rgups.edu.mps pr
    ON vp.s_prot = pr.idz
   AND pr.DATA = '09.08.2017'
 INNER JOIN isu_umu.inddiscip@asunt1_u.rgups.edu.mps i
    ON i.s_varplan = vp.idz
 INNER JOIN isu_umu.uch_discip@asunt1_u.rgups.edu.mps ud
    ON ud.s_inddiscip = i.idz
   AND ud.s_grvzanat = 1
   INNER JOIN iss_spr.vdiscip@asunt1_spr vd ON vd.idz=ud.s_fur
 WHERE vp.idz >= 27620
 ORDER BY 1,2, 3;