查询距离系统时间1秒、1分、1小时、1天的两种写法

--1.使用interval
select trunc(sysdate) + (interval '1' second) * 1  from dual;
select trunc(sysdate) + (interval '1' minute) * 1  from dual;
select trunc(sysdate) + (interval '1' hour) * 1    from dual;
select trunc(sysdate) + (interval '1' day) * 1     from dual;

--2.一般写法
select sysdate + 1/24/60/60 from dual;
select sysdate + 1/24/60    from dual;
select sysdate + 1/24       from dual;
select sysdate + 1          from dual;