Обсуждение: timestamp with time zone

Hi,

Can someone enlighten me?

I know that I can insert date/time data along with time zone info into
the timestamp with time zone data type. My question is, can I extract
the *original* time zone info afterward? I seems impossible.

May be I should use date + time with time zone to preserve the time
zone info?

It seems the time with time zone data type can do this.

test=# create table t2(t time with time zone);
CREATE TABLE
test=#
test=# insert into t2 values('12:34:56 +0400');
INSERT 0 1
test=# select * from t2;
      t
-------------
 12:34:56+04
(1 row)

test=# select t at time zone 'jst' from t2;
  timezone
-------------
 17:34:56+09
(1 row)

test=# select t::time from t2;
    t
----------
 12:34:56
(1 row)
--
Tatsuo Ishii
SRA OSS, Inc. Japan

On Dec 12, 2007 11:10 PM, Tatsuo Ishii <ishii@sraoss.co.jp> wrote:
> Hi,
>
> Can someone enlighten me?
>
> I know that I can insert date/time data along with time zone info into
> the timestamp with time zone data type. My question is, can I extract
> the *original* time zone info afterward? I seems impossible.

Yep, that's correct.  Basically, when you store a timestamp with
timezone, postgresql converts it to UTC and stores that.  when you get
it back, it converts it to the timezone of the client currently
connected. If you want to store the timezone you'll have to create
another field to hold that.