Обсуждение: TO_DATE behavior!

I would like to have your opinion about the following behavior of TO_DATE.
Is this correct or a hidden feature?

case:
'mon 21-feb-2008' is obviously a bad date. It should be 'thu 21-feb-2008'

test:
testdb=# select to_date('mon 21-feb-2008','dy dd-mon-yyyy'); to_date
------------2008-02-21
(1 row)

No complains there!(?)

The opposite query results the correct date.

test:
testdb=# select to_char(to_date('mon 21-feb-2008','dy dd-mon-yyyy'),'dy
dd-mon-yyyy');    to_char
-----------------thu 21-feb-2008
(1 row)


Regards,
Gevik 

Gevik Babakhani wrote:
> I would like to have your opinion about the following behavior of TO_DATE.
> Is this correct or a hidden feature?

There are quite a few complaints in the archive about to_date's incorrect or 
questionable behavior.  I'm sure this is one of them.  This code needs a 
general, systematic review.

-- 
Peter Eisentraut
http://developer.postgresql.org/~petere/

> There are quite a few complaints in the archive about 
> to_date's incorrect or questionable behavior.  I'm sure this 
> is one of them.  This code needs a general, systematic review.

I am working on a todo item. I'll report and fix anything I encounter there.

Regards,
Gevik 

Peter Eisentraut <peter_e@gmx.net> writes:
> Gevik Babakhani wrote:
>> I would like to have your opinion about the following behavior of TO_DATE.
>> Is this correct or a hidden feature?

> There are quite a few complaints in the archive about to_date's incorrect or 
> questionable behavior.  I'm sure this is one of them.  This code needs a 
> general, systematic review.

to_date has always been impressively lax about error-checking its input.
While I wouldn't object to tightening that up, surely checking a
weekday name against the rest of the date should be very far down the
priority list of checks to make.
        regards, tom lane