select sysdate from dual;--2018/10/30 8:54:51
select trunc(sysdate) from dual; --2018/10/30
select to_char(trunc(sysdate)) from dual; --30-OCT-18
select to_char(sysdate,'yyyymmdd') from dual;--20181030
select sysdate from dual;--2018/10/30 8:54:51
select trunc(sysdate) from dual; --2018/10/30
select to_char(trunc(sysdate)) from dual; --30-OCT-18
select to_char(sysdate,'yyyymmdd') from dual;--20181030