Query 1.1 Review


Overall, the draft looks very good. I have some detailed comments below.


** General Questions:

1) What is the expected behavior for GRAPH queries inside GRAPH queries 
(this nesting could occur in a lot of situations)?
I couldn't find a discussion of this in the docs.

For example,
{ GRAPH ?g1 { ?a :p1 ?b GRAPH ?g2 { ?c :p2 ?d } }

Does triple ?c :p2 ?d have to belong to both g1 and g2, or only g2, etc.

** Section 8 Negation:

1) Why have different variable scope for FILTER and non-FILTER cases for 
EXISTS and NOT EXISTS? What would we lose by having the non-filter form 
apply to the whole group in which the EXISTS / NOT EXISTS appears 
instead of only variables defined earlier in the pattern? I'm not sure 
why we need this extra complication.

** Section 13.1.2 SELECT expressions:

1) As far as SPARQL grammar is concerned, is "Expression" here the same 
as "Expression" in FILTER and ORDER BY? If so, that answers the next 

1) Are constants allowed in SELECT expressions (e.g. SELECT ?s 
(<http://myProp> as ?p) ?o WHERE ... )? If so, it may be worth adding an 
example with a constant.

** Minor Comments:

1) In "Status of this Document": "In this publication,
      new content is gathered together for ** easy => ease ** of review 
of these new features."

Received on Monday, 4 January 2010 21:51:51 UTC