1ALTER SESSION SET NLS_LANGUAGE=english; -- First day of week
2SELECT
3 -- Last Sunday of October at 02:00
4 NEXT_DAY(LAST_DAY(TO_DATE(TO_CHAR('01/10/'
5 || (EXTRACT(YEAR FROM SYSDATE)-5 + level) || '02:00:00'),
6 'DD/MM/YYYY HH24:MI:SS')) - INTERVAL '7' DAY, 'SUNDAY') AS H_WINTER,
7 -- Last Sunday of March at 02:00 (missing hour)
8 NEXT_DAY(LAST_DAY(TO_DATE(TO_CHAR('01/03/'
9 || (EXTRACT(YEAR FROM SYSDATE)-5 + level) || '02:00:00'),
10 'DD/MM/YYYY HH24:MI:SS')) - INTERVAL '7' DAY, 'SUNDAY') AS H_SUMMER
11FROM DUAL CONNECT BY level <=10;