가변 컬럼은 정적 쿼리로는 불가능합니다.
최대 가능개수 만큼 고정으로 구현하세요.
가변으로 구현하려면 동적 쿼리.
 

SELECT cht_no
     , eqp_no
     , main_sort_code
     , MIN(CASE rn WHEN 1 THEN sort_def_code END) sort_1
     , MIN(CASE rn WHEN 2 THEN sort_def_code END) sort_2
     , MIN(CASE rn WHEN 3 THEN sort_def_code END) sort_3
     , MIN(CASE rn WHEN 4 THEN sort_def_code END) sort_4
     , MIN(CASE rn WHEN 5 THEN sort_def_code END) sort_5
     , MIN(CASE rn WHEN 6 THEN sort_def_code END) sort_6
     , MIN(CASE rn WHEN 7 THEN sort_def_code END) sort_7
     , MIN(CASE rn WHEN 8 THEN sort_def_code END) sort_8
     , MIN(CASE rn WHEN 9 THEN sort_def_code END) sort_9
  FROM (SELECT t.cht_no
             , t.eqp_no
             , z1.sort_def_code AS main_sort_code
             , z2.sort_def_code
             , ROW_NUMBER() OVER(PARTITION BY t.cht_no, t.eqp_no, z1.sort_def_code
                                     ORDER BY z2.sort_def_code) rn
          FROM (SELECT cht_no
                     , eqp_no
                     , line_code 
                  FROM mp_sms_unit_mst
                 WHERE cht_use_yn = 'Y'
                 UNION ALL
                SELECT b.sub_cht_no
                     , a.eqp_no
                     , a.line_code
                  FROM mp_sms_unit_mst a
                  LEFT JOIN mp_sms_unit_dtl b
                    ON a.id = b.parent_id
                 WHERE sub_cht_use_yn = 'Y'
                ) t
          LEFT JOIN mp_sms_op_sort_code z1
            ON z1.line_code    = t.line_code
           AND z1.cht_no       = t.cht_no
           AND z1.line_op_type = '01-HUB-01'
          LEFT JOIN mp_sms_op_dtl z2
            ON z2.line_code    = t.line_code
           AND z2.cht_no       = t.cht_no
           AND z2.line_op_type = '01-HUB-01'
         WHERE t.line_code = '01'
        ) a
 GROUP BY cht_no, eqp_no, main_sort_code
;