On 08/07/2014 11:36 AM, Kevin Grittner wrote:
> Steve Clark <sclark@netwolves.com> wrote:
>
>> I am confused by how postgres 8,4..13 is sorting my data.
>> select * from test order by data;
>> data
>> ----------
>>
>> -
>> --
>> 1
>> 11
>> 11F
>> 1F
>> a
>> b
>> C
>> F
>> -F
>> Feneric
>> Generic
>> (14 rows)
>>
>> The first row is a single space, the next row a single -, the next two -- .
>> What I don't understand is why the '-F', the ' Feneric' and
>> the ' Generic' sort where they do.
>>
>> I would expect the output to be like this:
>>
>> data
>> ----------
>>
>> Feneric
>> Generic
>> -
>> --
>> -F
>> 1
>> 11
>> 11F
>> 1F
>> a
>> b
>> C
>> F
>> (14 rows)
>> lc_collate
>> -------------
>> en_US.UTF-8
> PostgreSQL uses the OS collations. What you are getting matches my
> Ubuntu 14.04 machine:
>
> kgrittn@Kevin-Desktop:~/pg/master$ echo $LANG
> en_US.UTF-8
> kgrittn@Kevin-Desktop:~/pg/master$ sort <<XXX
>> Feneric
>> Generic
>> -
>> --
>> -F
>> 1
>> 11
>> 11F
>> 1F
>> a
>> b
>> C
>> F
>> XXX
> -
> --
> 1
> 11
> 11F
> 1F
> a
> b
> C
> F
> -F
> Feneric
> Generic
>
> --
> Kevin Grittner
> EDB: http://www.enterprisedb.com
> The Enterprise PostgreSQL Company
>
Hi Kevin,
Thanks for the response. I get the same thing as postgres if I sort from the command line too. But I don't understand
why.
I would expect '-F' to sort immediately after '-' and '--' not after 'F' as
well as ' Feneric' (spaceFeneric) and ' Generic' (spaceGeneric) to sort immediately after ' ' (space).
It is like the space character and the - in -Letter is ignored.
--
Stephen Clark
