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Re: ISSUE-48: Less verbose delete syntax

From: Andy Seaborne <andy.seaborne@talis.com>
Date: Fri, 6 Nov 2009 10:26:44 +0000
Message-ID: <58495e3d0911060226s675903a9q772ea12d6fe737f8@mail.gmail.com>
To: Kjetil Kjernsmo <kjetil@kjernsmo.net>
Cc: public-rdf-dawg@w3.org
Consider:

DELETE { ?x :p ?o }
DELETE { ?x :p ?o } WHERE { ?x :p o . FILTER(?o = <doesnotexist> }

which might arise from either using DELETE for INSERT by mistake the
second time or other bad editting

Assuming the INSERT is optional as well, which I think is the intent,
we have to be a bit careful about creating traps for the unwary:

And DELETE without WHERE is potentially ambiguous as a grammar and
certainly optically:

DELETE
INSERT
WHERE

Is that one request
  DELETE-INSERT-WHERE
or two
  DELETE
  INSERT-WHERE

What about missing the template out instead:

DELETE WHERE {?x :p ?o }

    Andy



2009/11/6 Kjetil Kjernsmo <kjetil@kjernsmo.net>:
> On Friday 6. November 2009 02:30:37 Axel Polleres wrote:
>> We didn't consider this particularly,
>
> OK!
>
>> but having the
>> WHERE part optional for a DELETE in that sense you propose
>> doesn't seem problematic to me, at first sight.
>
> Yeah, it breaks the earlier assumption that all variables needs to be bound
> in the WHERE clause, but since the value in this case will not be returned,
> it will simply be deleted, I think it looks like a nice way to resolve
> ISSUE-48.
>
> Cheers,
>
> Kjetil
> --
> Kjetil Kjernsmo
> kjetil@kjernsmo.net
> http://www.kjetil.kjernsmo.net/
>
>
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Received on Friday, 6 November 2009 10:27:26 GMT

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