SELECT TO_NUMBER(TO_DATE(‘2015-01-01 05:00:00‘, ‘YYYY-MM-DD HH24:MI:SS‘) - TO_DATE(‘1970-01-01 8:0:0‘, ‘YYYY-MM-DD HH24:MI:SS‘)) * 24 * 60 * 60 FROM DUAL;
秒转日期
SELECT TO_DATE(‘1970-1-1 8:0:0‘,‘YYYY-MM-DD HH24:MI:SS‘)+(1430020800/(3600*24)) FROM DUAL
摘自:http://www.cnblogs.com/linn/p/4533541.html
原文：https://www.cnblogs.com/jiafeimao-dabai/p/10648004.html