SELECT TO_CHAR(ADD_MONTHS(TRUNC(SYSDATE), -3), 'YYYYMM') || '01' AS STR_DY , TO_CHAR(ADD_MONTHS(TRUNC(SYSDATE), -1), 'YYYYMM') || TO_CHAR(LAST_DAY(ADD_MONTHS(TRUNC(SYSDATE), -1)), 'DD') AS END_DY , TO_CHAR(ADD_MONTHS(TRUNC(SYSDATE)-365, -3), 'YYYYMM') || '01' AS STR_DY2 , TO_CHAR(ADD_MONTHS(TRUNC(SYSDATE)-365, -1), 'YYYYMM') || TO_CHAR(LAST_DAY(ADD_MONTHS(TRUNC(SYSDATE)-365, -1)), 'DD') AS END_DY2 , TO_CHAR(TO_DATE(TO_CHAR(ADD_MONTHS(TRUNC(SYSDATE), -3), 'YYYYMM') || '01', 'YYYYMMDD'), 'J') AS J_STR_DY , TO_CHAR(TO_DATE(TO_CHAR(ADD_MONTHS(TRUNC(SYSDATE), -1), 'YYYYMM') || TO_CHAR(LAST_DAY(ADD_MONTHS(TRUNC(SYSDATE), -1)), 'DD'), 'YYYYMMDD'), 'J') AS J_SEND_DY , TO_CHAR(TO_DATE(TO_CHAR(ADD_MONTHS(TRUNC(SYSDATE)-365, -3), 'YYYYMM') || '01', 'YYYYMMDD'), 'J') AS J_SSTR_DY2 , TO_CHAR(TO_DATE(TO_CHAR(ADD_MONTHS(TRUNC(SYSDATE)-365, -1), 'YYYYMM') || TO_CHAR(LAST_DAY(ADD_MONTHS(TRUNC(SYSDATE)-365, -1)), 'DD'), 'YYYYMMDD'), 'J') AS J_SEND_DY2 FROM DUAL; Julian date 형식을 사용해 본적이 없지만...저렇게 값을 구해와서 하면 되지 않을까요?