Re: SPARQL Update feature

On 15 Jul 2010, at 20:44, Andy Seaborne wrote:

> Grammar updated:
> 
> [37]    Clear  	  	::=    	'CLEAR' 'SILENT'? GraphRefAll
> [38]   	Drop 	  	::=   	'DROP' 'SILENT'? GraphRefAll
> [39]   	Create 	  	::=   	'CREATE' 'SILENT'? GraphRef
> [40]   	GraphRef 	::=   	'GRAPH' IRIref
> [41]   	GraphRefAll 	::=   	GraphRef | 'DEFAULT' | 'NAMED' | 'ALL'
> 

Thanks, Update document updated in CVS

Alex.

> 	Andy
> 
> On 15/07/2010 3:19 PM, Alexandre Passant wrote:
>> Hi,
>> 
>> On 13 Jul 2010, at 14:39, Andy Seaborne wrote:
>> 
>>> 
>>> 
>>> On 13/07/2010 1:25 PM, Steve Harris wrote:
>>>> On 2010-07-13, at 11:46, Alexandre Passant wrote:
>>>> 
>>>> [ snip, all looks good to me ]
>>>> 
>>>>> We initially thought that ALL includes also the default graph, but that will be a problem for removing all named graphs but not the default one (not sure that will happen so often, yet)
>>>>> So better to have ALL = all named graphs, which leads to the following to clean the store
>>>>> 
>>>>> DROP ALL
>>>>> DROP DEFAULT
>>>>> 
>>>>> or
>>>>> 
>>>>> DROP ALL
>>>>> CLEAR DEFAULT
>>>>> 
>>>>> What do you think ?
>>>> 
>>>> I prefer DROP/CLEAR ALL does everything, including the default graph. "ALL" implies that to me.
>>> 
>>> I'm comfortable with that.
>>> 
>>> Another possibility for completeness: a special form like
>>> 
>>> RESET STORE
>>> 
>>> that then puts it outside the issue of whether ALL is all named graphs or all graphs.
>> 
>> Following the discussion on the last t-con on the ability to removed named graph (but not default) but also to remove all graphs, I suggest (as followed-up by Lee):
>> 
>> DROP [ SILENT ] (GRAPH<uri>  | DEFAULT | NAMED | ALL)
>> 
>> DROP DEFAULT : remove only default graph. It's dropped but implicitely re-created.
>> DROP NAMED : remove all named graphs
>> DROP ALL : remove all graphs (i.e. named graphs + default one) - RESET STORE could be an alias, but it introduces one more operation, which may not be useful in that case
>> 
>> And use the same operations (including SILENT) for the CLEAR.
>> As discussed previously, DROP DEFAULT == CLEAR DEFAULT (since default graph must exist, it's implicitly created after being DROPped), but I find more consistent to use same grammar for both.
>> 
>> Alex.
>> 
>>> 
>>>> 
>>>> If I really want to leave the named graph, and CLEAR the others I can do that with:
>>>> 
>>>> DELETE WHERE { GRAPH ?g { ?x ?y ?z } }
>>>> 
>>>> Admittedly there's no DROP equivalent, for graphs that don't do empty graph culling, but that's well into corner cases AFAIC.
>>> 
>>> It's not a corner case for me - some implementations are quite happy with empty graphs and they don't naturally get culled.  Such grah stores are a collection of graphs, not stored in a common quad table.
>>> 
>>>> 
>>>> Otherwise, you could add a "GRAPH *" like syntax, meaning all named graphs, but I predict that users would confuse GRAPH * and ALL a lot.
>>> 
>>> Maybe - I'm more comfortable with DROP GRAPH *. With an explicit use of GRAPH, and DEFAULT (not GRAPH DEAFULT) it makes sense and is explainable.  At least "DROP GRAPH *" does not destroy data that the user didn't want addressed.
>>> 
>>> 	Andy
>>> 
>>>> 
>>>> - Steve
>>>> 
>>>> --
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>> 
>> --
>> Dr. Alexandre Passant
>> Digital Enterprise Research Institute
>> National University of Ireland, Galway
>> :me owl:sameAs<http://apassant.net/alex>  .
>> 
>> 
>> 
>> 
>> 
>> 

--
Dr. Alexandre Passant
Digital Enterprise Research Institute
National University of Ireland, Galway
:me owl:sameAs <http://apassant.net/alex> .

Received on Friday, 16 July 2010 16:31:59 UTC