- From: Andy Seaborne <andy@apache.org>
- Date: Sun, 27 Jul 2014 18:40:46 +0100
- To: Sandro Hawke <sandro@w3.org>, public-ldp-wg@w3.org
On 27/07/14 18:06, Sandro Hawke wrote:
> On 07/27/2014 12:33 PM, Sandro Hawke wrote:
>> On 07/27/2014 11:47 AM, Andy Seaborne wrote:
>>> On 27/07/14 16:12, Sandro Hawke wrote:
>>>> 1. I realized allowing single-use blank nodes in the DELETE clause
>>>> gives us the wildcard functionality I really want, so I can say:
>>>>
>>>> PREFIX x: <something...>
>>>> DELETE DATA {
>>>> x:me x:name []
>>>> }
>>>> INSERT DATA {
>>>> x:me x:name "John Smith"
>>>> }
>>>
>>> but it is then not SPARQL Update semantics. You would need DELETE
>>> WHERE.
>>>
>>
>> Rats, I guess that's why I left it out earlier. Thanks for the catch.
>>
>> I suppose we could add a WHERE clause that's restricted to containing
>> exactly the triples in the DELETE DATA clause which contain
>> variables. I think that would do the right thing in SPARQL, and a
>> non-SPARQL processor could ignore it and treat variables as wildcards.
>>
>> So, that would make patches a little longer, and it would make the
>> syntax of the DELETE DATA clause be Turtle + ?variables, not just Turtle.
>>
>
> Double ARG -- I replied too quickly. You were saying, I think, that I
> just need to use DELETE WHERE instead of DELETE DATA, not that I need a
> whole duplicate WHERE clause.
Yes, but
DELETE WHERE { x:me x:name ?var }
which is shorthand for
DELETE { x:me x:name ?var } WHERE { x:me x:name ?var }
No blank nodes allowed (because it's not a shorthand).
The cost of an update is in danger of being being opened up though.
(I'm not following closely enough but from what I can tell there are
variations on the design requirements in the active threads, or at least
different emphasises at different times.)
Andy
>
> Thanks!!
>
> -- Sandro
>
>
>>> Andy
>>>
>>> PS Is human read/writeablity a requirement for LDP-Patch?
>>>
>>>
>>
>>
>> No, I don't think so.
>>
>> -- Sandro
>>
>>
>>
>
Received on Sunday, 27 July 2014 17:41:16 UTC