select screqiv_subj_code,
screqiv_crse_numb new_number,
screqiv_crse_numb_eqiv old_number
from screqiv a
where screqiv_crse_numb_eqiv like '%X'
and screqiv_subj_code = screqiv_subj_code_eqiv
and screqiv_eff_term = (select max(b.screqiv_eff_term)
from screqiv b
where a.screqiv_subj_code = b.screqiv_subj_code
and a.screqiv_crse_numb = b.screqiv_crse_numb)