- From: Andy Seaborne <andy.seaborne@epimorphics.com>
- Date: Fri, 31 Dec 2010 13:19:59 +0000
- To: Steve Harris <steve.harris@garlik.com>
- CC: Lee Feigenbaum <lee@thefigtrees.net>, SPARQL Working Group <public-rdf-dawg@w3.org>
On 23/12/10 12:09, Steve Harris wrote:
> On 2010-12-23, at 11:58, Andy Seaborne wrote:
>>>
>>> I had an action to look at including CONSTRUCT WHERE { ... } for commonality with DELETE WHERE. I've not done anything about that, but it looks to me like it could be included as:
>>>
>>> 'CONSTRUCT WHERE' GroupGraphPattern SolutionModifier
>>
>> See discussion:
>> http://lists.w3.org/Archives/Public/public-rdf-dawg/2010OctDec/0462.html
>
> I completely forgot that.
>
> In that case, modulo the stuff I've already mentioned, I think it's OK.
>
> - Steve
In the spirit of facts, and not mere guesswork, I went back and checked
on the implications of a "CONSTRUCT WHERE" short form. It's doable: my
fears were unfounded.
Based on the discussion around DELETE WHERE, I have only considered a
BGP or construct template for the WHERE clause. No FILTER, no other
graph patterns.
It's not quite like DELETE WHERE because of FROM/FROM NAMED.
It can be done by only changing the rule for CONSTRUCT:
[9] ConstructQuery ::=
'CONSTRUCT'
(
# The original rule
ConstructTemplate DatasetClause* WhereClause SolutionModifier
|
# The short form.
DatasetClause* 'WHERE' '{' TriplesTemplate? '}' SolutionModifier
)
It may be possible to tidy this up.
In the short form WHERE is mandatory - this enables the parser to know
it's skipped the template in the full form.
Therefore, I think we should put this in. The extra editing is quite
small - adding a short para and example query to the CONSTRUCT section.
Andy
Received on Friday, 31 December 2010 13:20:40 UTC