Change SYSDATE for testing

This morning I had some free time, so I was playing around with a little APEX 4 plugin. Probably the most simple plugin that you can imagine, but that is not what this post is about, or at least not mainly.
The plugin shows the current date (or I should say: sysdate) as a region on an APEX page.


Of course I needed to make sure that it works as SYSDATE changes. Of course I am not refering to the changing of the time component of SYSDATE.
To change SYSDATE you can use this command. Note that it changes SYSDATE for the whole system.

SQL> alter system set fixed_date ='2011-08-05'
  2  /

System altered.

Querying SYSDATE from SQL*Plus will show the effect:

SQL> select sysdate
  2    from dual
  3  /

SYSDATE
---------
05-AUG-11

Also note that SYSDATE is now fixed, not even the time component changes:

SQL> alter session set nls_date_format = 'dd-mm-yyyy hh24:mi:ss'
  2  /

Session altered.

SQL> select sysdate
  2    from dual
  3  /

SYSDATE
-------------------
05-08-2011 00:00:00

SQL> /

SYSDATE
-------------------
05-08-2011 00:00:00

Refreshing the APEX page also reflects the changed SYSDATE.


To restore the real SYSDATE, issue this command.

SQL> alter system set fixed_date = none
  2  /

System altered.

SQL> select sysdate
  2    from dual
  3  /

SYSDATE
-------------------
03-11-2010 10:53:40

I knew about this functionality, but never thought I would actually need it.
If you want the plugin, you can download it by following this link.