Re: BUG #6638: Casablanca timezone is wrong

The following bug has been logged on the website:

Bug reference: 6638
Logged by: David Chuet
Email address: dchuet(at)odotech(dot)com
PostgreSQL version: 9.0.7
Operating system: Windows 7 x64
Description:

Using Postgresql command :

------------------------------------------
SELECT * FROM pg_timezone_names
------------------------------------------
We get for Africa/Casablanca, timezone equal to WET with no DST.

This is not true from 2010.
See Wikipedia, for Morocco:

Time zone WET (UTC+0)
Summer (DST) WEST (UTC+1)(May 2nd to August 7th)

So, I cannot set correctly the DateTime for an install in Morocco.

dchuet(at)odotech(dot)com writes:
> We get for Africa/Casablanca, timezone equal to WET with no DST.
> This is not true from 2010.
> See Wikipedia, for Morocco:

I wouldn't necessarily trust Wikipedia for that. We use the IANA
(nee Olson) timezone database. If you think the information in that
is wrong, you should take it up with the upstream maintainers:
http://www.iana.org/time-zones

As far as I can tell from a quick look in their mailing list archives,
the timezone data shipped with 9.0.7 is correct for Morocco through
2011. It does not know about the 2012 DST law that was just published
a few weeks ago, but unless you can provide use of a time machine,
there's not a lot we can do about that. We customarily update to the
latest timezone data files available from IANA whenever Postgres update
releases are made. If you are in a bigger hurry than that, you can get
the latest tzdata files from the above-mentioned page and drop them into
the timezone directory in your installation.

regards, tom lane

On 14.05.2012 18:21, dchuet(at)odotech(dot)com wrote:
> We get for Africa/Casablanca, timezone equal to WET with no DST.
>
> This is not true from 2010.
> See Wikipedia, for Morocco:
>
> Time zone WET (UTC+0)
> Summer (DST) WEST (UTC+1)(May 2nd to August 7th)

PostgreSQL uses the timezone data from the so-called Olson library. See
http://www.twinsun.com/tz/tz-link.htm. Looking at the upstream library,
this is fixed in the most recent version (tzdata2012c), We will pick up
that change in the next PostgreSQL minor release, ie. 9.0.8 for the 9.0
series.

--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com

Thanks guys for your prompt support!
I'm going to update Olson library on the concerned computer using the latest files.

Thanks again.

David Chuet
Odotech inc.

-----Original Message-----
From: Heikki Linnakangas [mailto:heikki(dot)linnakangas(at)enterprisedb(dot)com]
Sent: May-14-12 11:51 AM
To: David Chuet
Cc: pgsql-bugs(at)postgresql(dot)org
Subject: Re: [BUGS] BUG #6638: Casablanca timezone is wrong

On 14.05.2012 18:21, dchuet(at)odotech(dot)com wrote:
> We get for Africa/Casablanca, timezone equal to WET with no DST.
>
> This is not true from 2010.
> See Wikipedia, for Morocco:
>
> Time zone WET (UTC+0)
> Summer (DST) WEST (UTC+1)(May 2nd to August 7th)

PostgreSQL uses the timezone data from the so-called Olson library. See http://www.twinsun.com/tz/tz-link.htm. Looking at the upstream library, this is fixed in the most recent version (tzdata2012c), We will pick up that change in the next PostgreSQL minor release, ie. 9.0.8 for the 9.0 series.

--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com