Re: PostgreSQL Timezone and Brazilian DST

On 10/27/2015 10:43 PM, Edson Richter wrote:
> ---- Adrian Klaver escreveu ----
>
>  > On 10/27/2015 07:29 PM, Edson Richter wrote:
>  > > Hi!
>  > >
>  > > Using PostgreSQL 9.3.10 x86_64 Oracle EL7 compiled by gcc (GCC) 4.8.3
>  > > 20140911, installed using yum repository.
>  > >
>  > > In postgresql.conf, I do have:
>  > >
>  > > timezone="America/Sao_Paulo"
>  > >
>  > > Since DST is in place in Brazil, it is enough to "systemctl reload
>  > > postgresql-9.3" to make it effective?
>  >
>  > Are you saying that you just changed the timezone setting or that time
>  > in Brazil just went from standard time to DST and you want to know
>  > whether Postgres will automatically pick that up with the existing
>  > setting as above?
>
> Configured since first setup. Brazil went DST few days ago.
> Today, executing
>
> Select now()
> Resulted in
>
> 2015-10-28 02:45:37-03:00
>
> I do expect
>
> 2015-10-28 03:45:37-02:00
>
> I suspect that Postgres is ignoring the DST change.


Well it works for me here:

test=> set timezone="America/Sao_Paulo";
SET
test=> select now();
               now
-------------------------------
  2015-10-28 11:30:21.050485-02


So first thing I would do is see what is actually set in client:

test=> show timezone;
      TimeZone
-------------------
  America/Sao_Paulo


If it is not what you think it should be then:

test=> select * from pg_settings where name = 'TimeZone';

-[ RECORD 1 ]---------------------------------------------------------------
name       | TimeZone
setting    | America/Sao_Paulo
unit       |
category   | Client Connection Defaults / Locale and Formatting
short_desc | Sets the time zone for displaying and interpreting time stamps.
extra_desc |
context    | user
vartype    | string
source     | session
min_val    |
max_val    |
enumvals   |
boot_val   | GMT
reset_val  | US/Pacific
sourcefile |
sourceline |

Here for more info:
http://www.postgresql.org/docs/9.3/interactive/view-pg-settings.html

In particular, context and source.


>
> I just want to know if reload or restart is enough to make Postgres get
> into track.

No, if the above does not indicate a problem, then the issue is
probably, as Francisco said, in the timezone definitions. The thing is,
you are on 9.3.10 which has the latest time zone data file:

http://www.postgresql.org/docs/9.3/interactive/release-9-3-10.html


Update time zone data files to tzdata release 2015g for DST law changes
in Cayman Islands, Fiji, Moldova, Morocco, Norfolk Island, North Korea,
Turkey, and Uruguay. There is a new zone name America/Fort_Nelson for
the Canadian Northern Rockies.



>
> Thanks,
>
> Edson
>
>  >
>  > > Or a complete restart is required?
>  > >
>  > > Thanks,
>  > >
>  >
>  >
>  > --
>  > Adrian Klaver
>  > adrian.klaver@aklaver.com <mailto:adrian.klaver@aklaver.com>
>  >
>  >
>  > --
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>


--
Adrian Klaver
adrian.klaver@aklaver.com