The following bug has been logged online:

Bug reference: 2046
Logged by: Chris
Email address: termi (AT) wp (DOT) pl
PostgreSQL version: 8.0
Operating system: Windows
Description: defective date_trunc
Details:

Postgresql 8.0

select date_trunc('week',TO_DATE('2005-01-01','yyyy-mm-dd'))


result


"2006-01-02 00:00:00+01"

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Chris wrote:

Upgrade to 8.0.4. This bug is fixed there.

alvherre=# select date_trunc('week',TO_DATE('2005-01-01','yyyy-mm-dd'));
date_trunc
------------------------
2004-12-27 00:00:00-03
(1 fila)

alvherre=# select version();
version
---------------------------------------------------------------------------------------------------------------
PostgreSQL 8.0.3 on i686-pc-linux-gnu, compiled by GCC gcc (GCC) 4.0.2 20050806 (prerelease) (Debian 4.0.1-4)
(1 fila)

alvherre=#

--
Alvaro Herrera http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.

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Chris wrote:
Are you on 8.0.4? If not, you need to upgrade because we fixed this.

--
Bruce Momjian | http://candle.pha.pa.us
pgman (AT) candle (DOT) pha.pa.us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073

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