How to get GMT or IST using PL/SQL FUNCTION

Question

Hello I am using Oracle 10G database (OS: Windows-32 and Windows-64).
How can i get the date and time GMT or International time without referring SYSDATE / DBDATE.
Actual problem the DB-Sever date/time is frequently manipulated by end user and i want to log the actual date and time of transaction in some audit table.
Regards,
Tarun

Answer 1

It won't increase your server load, you'd simply have a lot of http wait events and the performance of your application would depend on your customers internet connection. Something not very desireable if you ask me, and most certainly will cause you headaches. Really bad headaches, and one day someone will ask who came up with the brilliant idea to get the system timestamp via http instead of...+sysdate+ (I smell a http://thedailywtf.com/ article coming up).
Anyway; here it goes: the http based sysdate function. I am using mod_plsql for my "webservice" running on a server from where I trust the date is correct. You can use anything you like, for a "real" webservice, the implementation will be a little bit different than that. Google would know the answer on how to call webservices from the database.
$[CHE_TEST@asterix1_impl] create or replace procedure server_time as
  2  begin
  3  htp.print(to_char(sysdate, 'dd.mm.yyyy hh24:mi:ss'));
  4  end;
  5  /
Procedure created.As you can see the procedure does nothing else then outputting the sysdate of my database server in a specified date format. Then, on a different server I call the mod_plsql procedure via utl_http:
$[CHE_TEST@asterix2_al32utf8] create or replace function get_server_time return date is
  2  begin
  3    --default would be 60, this is clearly too much
  4    utl_http.set_transfer_timeout(1);
  5    return to_date(utl_http.request('http://ias4/asterix1_impl_cronet/server_time'), 'dd.mm.yyyy hh24:mi:ss');
  6  exception
  7    when utl_http.REQUEST_FAILED then
  8      return sysdate;
  9  end;
10
11  /
Function created.Now get_server_time will give me the time of my first database server (except the HTTP Request fails for some reason, then it'll be sysdate)
$[CHE_TEST@asterix2_al32utf8] select get_server_time from dual;
GET_SERVER_TIME
24.07.2012 13:35:00Again if you are going down that road use the function carefully and not in every end of your application as it will give you performance problems.
cheers