> -----Original Message-----
> From: Tom Lane [mailto:tgl@sss.pgh.pa.us]
> Sent: Thursday, October 20, 2005 2:54 PM
> To: Dann Corbit
> Cc: Richard_D_Levine@raytheon.com; general@postgresql.org; pgsql-
> hackers@postgresql.org
> Subject: Re: [GENERAL] [HACKERS] 'a' == 'a '
>
> "Dann Corbit" <DCorbit@connx.com> writes:
> > I guess that additional ambiguity arises if you add additional
spaces to
> > the end. Many database systems solve this by trimming the
characters
> > from the end of the string upon storage and the returned string will
not
> > have any trailing blanks.
>
> Can you document that? ISTM that that would effectively make char(n)
> and varchar(n) exactly equivalent, which is ... um ... a bit stupid.

This is SQL*Server:

drop table test_char
go
create table test_char(
fixed_30 char(30),
varch_30 varchar(30),
nchar_30 nchar(30),
nvarc_30 nvarchar(30)
)
go
insert into test_char values('Dann ', 'Dann ', 'Dann ', 'Dann ')
go
select len(fixed_30), len(varch_30), len(nchar_30), len(nvarc_30)
from test_char
go

Result set:
4 4 4 4


---------------------------(end of broadcast)---------------------------
TIP 4: Have you searched our list archives?

http://archives.postgresql.org

Dann Corbit wrote:

>>-----Original Message-----
>>From: Tom Lane [mailto:tgl@sss.pgh.pa.us]
>>Sent: Thursday, October 20, 2005 2:54 PM
>>To: Dann Corbit
>>Cc: Richard_D_Levine@raytheon.com; general@postgresql.org; pgsql-
>>hackers@postgresql.org
>>Subject: Re: [GENERAL] [HACKERS] 'a' == 'a '
>>
>>"Dann Corbit" <DCorbit@connx.com> writes:
>>
>>
>>>I guess that additional ambiguity arises if you add additional
>>>
>>>
>spaces to
>
>
>>>the end. Many database systems solve this by trimming the
>>>
>>>
>characters
>
>
>>>from the end of the string upon storage and the returned string will
>>>
>>>
>not
>
>
>>>have any trailing blanks.
>>>
>>>
>>Can you document that? ISTM that that would effectively make char(n)
>>and varchar(n) exactly equivalent, which is ... um ... a bit stupid.
>>
>>
>
>This is SQL*Server:
>
>drop table test_char
>go
>create table test_char(
> fixed_30 char(30),
> varch_30 varchar(30),
> nchar_30 nchar(30),
> nvarc_30 nvarchar(30)
>)
>go
>insert into test_char values('Dann ', 'Dann ', 'Dann ', 'Dann ')
>go
>select len(fixed_30), len(varch_30), len(nchar_30), len(nvarc_30)
>from test_char
>go
>
>Result set:
>4 4 4 4
>
>
>
>

Yech.

What does one do in such a system if you want trailing blanks to be
significant, or even kept?

Anyway, the consensus seems to be that Postgresql's behavious is
consistent with a reasonable reading of the standard, so is there
anything really left to discuss, other than a possible addition to
documentation?

cheers

andrew



---------------------------(end of broadcast)---------------------------
TIP 6: explain analyze is your friend