注意是用1970/1/1的8點:
用sql獲取當前秒數:
SELECT (CAST(SYS_EXTRACT_UTC(SYSTIMESTAMP) AS DATE) - TO_DATE('01/01/1970 08:00:00','dd/mm/yyyy hh24:mi:ss')) * 24 * 60 * 60 FROM DUAL
當月一號秒數:
SELECT (trunc(sysdate,'mm')- TO_DATE('01/01/1970 08:00:00','dd/mm/yyyy hh24:mi:ss')) * 24 * 60 * 60 FROM DUAL