The interchange ____oracle of long and date in Oracle

If the Oracle database Time field is set to the number type, the query time column is presented as a numeric value, such as the "1241450728000" style, is not readable, and the "2009/5/4 15:25:28" style update time prompts " Ora-01722:invalid number ", cannot be updated.

At this point, we need to format this, examples are as follows:

--date Long Example
select Sysdate (sysdate-to_date (' 1970-01-01 ', ' yyyy-mm-dd ')) * 24*60*60*1000 as integral format from dual;
 
--long to date
select  to_date (' 1970-01-0100:00:00 ', ' yyyy-mm-dd hh24:mi:ss ') + 1241450728000/1000/24/60/60 from  dual;