Re: ISSUE-35: DISTINCT/aggregates

On 3 Feb 2010, at 14:09, Andy Seaborne wrote:
> On 03/02/2010 12:15 PM, Steve Harris wrote:
>> On 3 Feb 2010, at 08:42, Andy Seaborne wrote:
>> ...
>>> ISSUE-35
>>> Can aggregate functions take DISTINCT as an argument a la SELECT
>>> COUNT(DISTINCT ?X)?
>>>
>>> DONE All built-in aggregates can take the word DISTINCT.
>>> Custom ones do not; it's part of their definition,
>>> i.e. different URIs for a DISTINCT and non DISTINCT form.
>>
>> I thought that the custom ones could also take DISTINCT? My  
>> recollection
>> may well be wrong though. Do you have a link to the strawpoll?
>
> By using a keyword argument, it undermines the idea that the URI  
> identifies one thing - it's really now two, the DISTINCT and non- 
> DISTINCT versions.
>
> I'd expect COUNT(*) and COUNT(DISTINCT *) to have different URIs.

Ah, interesting, I wouldn't.

E.g. GROUP_CONCAT(DISTINCT ?x ORDER BY STRLEN(?x)) wouldn't have a  
different URI to GROUP_CONCAT(DISTINCT ?x) either.

In my mind the DISTINCT is part of the expression, not part of the  
function.

- Steve

Received on Wednesday, 3 February 2010 15:11:33 UTC