To: pgsql-sql@postgresql.org
From: Jasen Betts <jasen@xnet.co.nz>
Subject: Re: to_char() accepting invalid dates?
Date: 18 Jul 2011 09:23:27 GMT
Organization: Dis (not Dat) Organisation
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On 2011-07-18, Thomas Kellerer <spam_eater@gmx.net> wrote:
> Hi,
>
> I just noticed that to_char() will "accept" invalid dates such as 2011-02-31 and "adjust" them accordingly:
>
> postgres=> select to_date('20110231', 'yyyymmdd');
>
>    to_date
> ------------
>   2011-03-03
> (1 row)
>
> is there a way to have to_date() raise an exception in such a case?

it's possible the odd behaviour you get is required by some standard.
however 'yyyymmdd' is a format that postgres understands natively,
so just cast the string to date.

 jasen=# select '20110303'::date;
     date    
  ------------
   2011-03-03
   (1 row)
		    
 jasen=# select '20110231'::date;
 ERROR:  date/time field value out of range: "20110231"
 LINE 1: select '20110231'::date;
                 ^

postgres also understands YYYY-MM-DD and possilby a locale 
dependant form with the year last 
		    
-- 
⚂⚃ 100% natural