SQL of contention for system time plus time in ocrale database

Make a note of , Change the time sql:

select sysdate,to_char(sysdate+1/24,'yyyy-mm-dd HH24:MI:SS') from dual; -- Add 1 Hours

-------------- Other ：
select sysdate,add_months(sysdate,12) from dual; -- Add 1 year
select sysdate,add_months(sysdate,1) from dual; -- Add 1 month
select sysdate,to_char(sysdate+7,'yyyy-mm-dd HH24:MI:SS') from dual; -- Add 1 week
select sysdate,to_char(sysdate+1,'yyyy-mm-dd HH24:MI:SS') from dual; -- Add 1 God
select sysdate,to_char(sysdate+1/24,'yyyy-mm-dd HH24:MI:SS') from dual; -- Add 1 Hours
select sysdate,to_char(sysdate+1/24/60,'yyyy-mm-dd HH24:MI:SS') from dual; -- Add 1 minute bai
select sysdate,to_char(sysdate+1/24/60/60,'yyyy-mm-dd HH24:MI:SS') from dual; -- Add 1 second