Oracle 23c

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ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS';
CREATE TABLE table_name (code, title) AS
  SELECT '1',           'abc'     FROM DUAL UNION ALL
  SELECT '1-1',         'kkk'     FROM DUAL UNION ALL
  SELECT '1-1-1',       'dfgf'    FROM DUAL UNION ALL
  SELECT '1-1-1-1',     'dfsd'    FROM DUAL UNION ALL
  SELECT '1-1-1-1-1',   'sdfsd'   FROM DUAL UNION ALL
  SELECT '1-1-1-1-1-1', 'sccdfsd' FROM DUAL;
6 rows affected

SELECT SUBSTR(SYS_CONNECT_BY_PATH(title, ', '), 3) AS titles
FROM   (
  SELECT code,
         title,
         LENGTH(code) - LENGTH(REPLACE(code, '-')) AS depth
  FROM   table_name
)
WHERE  CONNECT_BY_ISLEAF = 1
START WITH
       depth = 0
CONNECT BY
       code LIKE PRIOR code || '-%'
AND    depth = PRIOR depth + 1;


TITLES


abc, kkk, dfgf, dfsd, sdfsd, sccdfsd