Re: to_date_valid()

On 15.08.2016 14:33, Andreas 'ads' Scherbaum wrote:
>> Is it right and "true" way to validate date by extra transforming and
>> comparison?
>>
>> Maybe validate date by using ValidateDate(). Attached sample patch.
>
> This does not solve the problem at hand, and let's wrong dates/formats
> slip through:
>
> ./buildclient.py -v -c demo-config-pg.yaml --run-configure --run-make
> --run-install --no-clean-at-all --patch
> 'https://www.postgresql.org/message-id/95738e12-6ed6-daf5-9dcf-6336072e6b15%40postgrespro.ru'
>
>
>
> postgres=# SELECT to_date('2011 12  18', 'YYYY MM   DD');
>   to_date
> ------------
>  2011-12-08
> (1 row)
>
>
> That is from the regression tests, and obviously handles the date
> transformation wrong. My attempt catches this, because I compare the
> date with the input date, and do not rely on a valid date only.

I suppose that your sample query is an another issue, not date validate 
task. I sent the patch to the thread 
https://www.postgresql.org/message-id/b2a39359-3282-b402-f4a3-057aae500ee7@postgrespro.ru 
. It fixes formatting issues.

I thought that it is better to distinguish this issues to:
- validation of input date/timestmap string and input format string
- result date/timestamp validation

-- 
Artur Zakirov
Postgres Professional: http://www.postgrespro.com
Russian Postgres Company