Thread: Bad date representation

Bad date representation

From
Roland_DUBOULOZ
Date:
Is there a bug in the postmaster ?
with -e option the date must be in European format
but with no options the date may be in European or American format !

create table FOO (date date);

1.- postmaster -i -o -e 
 insert into FOO values('20-06-1999');  insert into FOO values('06-21-1999'); we have a "Bad date external
representation"that is true.
 

2.-postmaster -i
 insert into FOO values('06-22-1999'); insert into FOO values('06-07-1999'); insert into FOO values('23-06-1999');
<----no ERROR  WE Have NO ERROR !!!!! why ???
 

and on select * from FOO the result is 
date ---------- 06-22-1999 06-07-1999 06-23-1999



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Roland Dubouloz            BULL XS/BU
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Re: [SQL] Bad date representation

From
Herouth Maoz
Date:
At 12:25 +0300 on 09/07/1999, Roland_DUBOULOZ wrote:


> 2.-postmaster -i
>
>   insert into FOO values('06-22-1999');
>   insert into FOO values('06-07-1999');
>   insert into FOO values('23-06-1999');  <---- no ERROR
>    WE Have NO ERROR !!!!! why ???
>
> and on select * from FOO the result is
>
>     date
>   ----------
>   06-22-1999
>   06-07-1999
>   06-23-1999

The way Postgres parses dates is: first, see if there is more than one way
to interpret the date. If there is more than one way, use the DateStyle.

So, if it sees a date like 23-06-1999, there is only one way to interpret
it - that the 23 is the day, and the 06 is the month. In that case, this is
June 23rd, and everything is OK. But a date like 08-06-1999 could be either
August sixth or June eighth. In that case, it uses the DateStyle to
determine which.

This algorithm gives you some lenience.

Herouth

--
Herouth Maoz, Internet developer.
Open University of Israel - Telem project
http://telem.openu.ac.il/~herutma