Re: Timestamp Problem

Hi Howard,

Thanks a lot for your reply. I really appreciate the time that you've taken to answer this, but my problem is different. It's more of an Java issue. The Timestamp that i retrieve is fine, but the JRE (Java Runtime Environment) is doing that conversion without my requesting it, and that's causing the problem.

Thanks again for your help though,
-Sagar.

"Howard J. Rogers" <dba_at_hjrdba.com> wrote in message news:<a7p2qq$4dk$1_at_lust.ihug.co.nz>...
> I'm no expert on Java (perish the thought), but what you describe happens to
> sound like the difference in 9i between the new 'timestamp with local time
> zone' and 'timestamp with time zone' data types. Both permit you to know
> that a record was entered at, say, 5pm Sydney time (in other words, 7am
> London time), but the former lets you know it by converting the timestamp
> for you into something that reads '7am', and the latter only lets you know
> it by displaying an invariant 5pm, but with a timezone indicator (such as
> "+10" or 'EDST') that lets you work it out if only you (or your app) does
> some calculating.
>
> For example:
>
> SQL> select sessiontimezone from dual;
>
> SESSIONTIMEZONE
> ---------------------------------------------------------------------------
> +11:00
>
> (which means I'm in the '11 hours ahead of GMT' timezone)
>
> SQL> create table timetest (col1 timestamp with local time zone, col2
> timestamp with time zone);
>
> Table created.
>
> (Note the two slightly different data types used for each column).
>
> SQL> insert into timetest values (sysdate, sysdate);
>
> 1 row created.
> SQL> commit;
> Commit complete.
>
> (The exact same time is now inserted into both).
>
> SQL> select * from timetest;
>
> COL1
> ---------------------------------------------------------------------------
> COL2
> ---------------------------------------------------------------------------
> 26/MAR/02 04:48:37.000000 PM
> 26/MAR/02 04:48:37.000000 PM +11:00
>
> (And both columns show the time as 4:48pm. However, the 'with time zone'
> version also includes visible details of which timezone I'm in).
>
> SQL> alter session set time_zone='America/New_York';
>
> Session altered.
>
> (Now imagine you're querying the record in New York).
>
> SQL> select * from timetest;
>
> COL1
> ---------------------------------------------------------------------------
> COL2
> ---------------------------------------------------------------------------
> 26/MAR/02 12:48:37.000000 AM
> 26/MAR/02 04:48:37.000000 PM +11:00
>
> You'll note that the second column hasn't changed. It shows exactly what
> the record would show if queried in Sydney. However, the inclusion of the
> "+11" means that, if you knew New York was 5 hours behind GMT, you could
> subtract 16 hours in total from the displayed clock time to arrive at the
> time it was in New York when I entered my record in Sydney. But you (and
> your app) have to do the conversion.
>
> On the other hand, the 'with local time zone' version has done the
> conversion for you automatically, and you see 12:48am displayed without
> further effort on your part.
>
> Now I don't know if you that's all a bunch of old hat to you, or whether
> it's got anything to do with Java at all, in which case apologies for
> wasting your time. But having got tripped up by accidentally missing out
> the one word 'local' myself, it's behaviour I've come to be frustrated
> about, and therefore wondered if it was of any relevance for you!
>
> Regards
> HJR
> --
> ------------------------------------------
> Resources for Oracle : www.hjrdba.com
> ============================
>
> "Sagar" <vkrishn_at_us.ibm.com> wrote in message
> news:ce13a44a.0203252052.472db901_at_posting.google.com...
> > Hi All,
> >
> > I have a java.sql.Timestamp object for instance 2002-03-22
> > 17:48:50.659. I get this value out when I use the regular JDK. Now I
> > have an RMI server and print out this Timestamp object by using a
> > toString() on it, and it prints the value just fine.
> >
> > Now, I pass this object to an applet (The applet calls the RMI server
> > which is printing the right value if I do a System.out and retrieves
> > the same object) and if I do a toString() on it with the same timezone
> > setting it prints the right value too (Note: the Applet client and the
> > RMI server are running on the same machine).
> >
> > Now if I change the timezone to CST, then the value that is printed by
> > the RMI server is the same (2002-03-22 17:48:50.659), but the value
> > that is printed on the applet if I do a toString on it is different
> > (2002-03-22 19:48:50.659).
> >
> > I understand that the JRE (I'm using 1.3.1_02, but a lot of JRE's that
> > I tried give the same problem) is trying the manipulate the Timestamp
> > object into the local time, but how come the SDK does'nt do it? I
> > guess that this is a problem with the JRE implementation, but I'm not
> > able to think of any fair way by which I can get around this problem.
> > Is there any way by which I can solve this?
> >
> > I thank you all in advance for any help that you might extend.
> >
> > Thanking you again,
> > Sagar.
Received on Tue Mar 26 2002 - 12:54:03 CST