Re: [GENERAL] 'a' == 'a '

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