- From: Howard Katz <howardk@fatdog.com>
- Date: Wed, 6 Oct 2004 08:57:38 -0700
- To: "Eric Prud'hommeaux" <eric@w3.org>
- Cc: "Dave Beckett" <dave.beckett@bristol.ac.uk>, "Dan Connolly" <connolly@w3.org>, "Andy Seaborne" <andy.seaborne@hp.com>, "Steve Harris" <S.W.Harris@ecs.soton.ac.uk>, "RDF Data Access Working Group" <public-rdf-dawg@w3.org>
Eric, I'll be out of office for the next 24 hours. If you have any questions for me I can answer them once I'm back. I've also got the SVG stuff under control and will be able to update your PNG's at that point. Howard > -----Original Message----- > From: public-rdf-dawg-request@w3.org > [mailto:public-rdf-dawg-request@w3.org]On Behalf Of Eric Prud'hommeaux > Sent: Wednesday, October 06, 2004 1:48 AM > To: Howard Katz > Cc: Dave Beckett; Dan Connolly; Andy Seaborne; Steve Harris; RDF Data > Access Working Group > Subject: Re: SPARQL / Language spec ready for review [Howard's feedback] > > > I said I'd get to this today. > I was wrong; had to play with the health inspections and immigration > servivces all day. I only just finished Daves and Howards will take > more attention than I have remaining. Should be back on in 8-10 hours. > > On Tue, Oct 05, 2004 at 07:12:27AM -0700, Howard Katz wrote: > > > > Hi Eric, > > > > This is done off a fairly quick read. I haven't tried to correlate my > > feedback against Dave's or anyone else's comments. I'm mostly > *not* doing a > > lot of nit-picking against spelling errors and other typos at > this point, > > ie, this is a bit of a higher-level view. This was reviewed > against 1.82. > > > > Hope it's useful, > > Howard > > > > ------------------------ > > 1 Introduction > > > > If you're having sub-headings, as in "Document Outline" and "Document > > Conventions", wouldn't it be more consistent to sub-number > them, as in "1.1" > > and "1.2"? > > > > --------------------- > > 2 Making Simple Queries > > > > Why not use the same data and query example(s) in the initial pictorial > > section and the following SPARQL syntax section? That way > readers would get > > a better feel for how one form translates into the other. > > > > ----------------------- > > last paragraph > > > > Where doesn't the "andy" come from? I don't see him in the graph above. > > > > ------------------------ > > 2.1 Writing a Simple Query > > > > Second paragraph, "The terms quoted ..." > > > > It's a fair distance from this sentence to the actual example > below, and the > > reader's eyes have to jump down to the example and then find > their way all > > the way back up again. Why not move this paragraph to either after the > > "Data:" section or after the "Query:" section? > > > > ---------------------- > > 2.2 Triple Patterns > > > > I'm not sure if this requires a bit of reorg or not, but all > the examples in > > the preceding section have WHERE clauses containing triple > patterns, but you > > don't introduce the concept until here. > > > > More importantly, you never say what a triple pattern IS (ie, something > > along the lines of "A template for describing an s-p-o triple, with > > variables representing missing information to be filled in by > the query" or > > some such. That would be very useful for reader. > > > > At a minimum, I'd change sentence one from > > "The building blocks of queries are triple patterns" > > to > > "The building blocks of queries are triple patterns, shown as > the arguments > > of the WHERE clauses in the three queries in the preceding section." > > > > --------------------- > > As well, a brief sentence explaining that triple patterns are > delimited by > > parentheses ("(" and ")") would be useful. > > > > -------------------- > > Paragraph 2, "A triple pattern has either a graph label > (URIRef, literal) or > > a named variable in each of the subject, predicate and object > positions." > > Literals of course can only go in the object position. Is it ok > to be this > > imprecise? (I'm asking because I don't know and don't have a strong > > opinion.) > > > > ---------------------- > > Definition: Triple Pattern > > "3" -> "three" > > > > ---------------------- > > 2.3 Graph Patterns > > First paragraph, "This starts with conjunction - the 'and' of triple > > patterns." > > > > It's not clear what "This ..." refers to. How about something > like, "We'll > > first look at conjunctions, which combine triple patterns using "and". > > > > ----------------------- > > Paragraph starting "There are is a bNode ..." > > > > 1) "are is" -> "is" > > > > 2) I don't understand the final clause in second sentence: ", nor to any > > query." > > > > ------------------------ > > 2.4 Multiple Matches > > > > "The results of query" -> "The results of a query" > > > > ------------------------ > > 4.2 Multiple Optional Blocks > > > > Second paragraph, you introduce the concept of outer block. > This hasn't been > > previously discussed, so it's unclear what this refers to. > Please define. As > > well, you follow with a hypothetical, "If a new variable is > introduced in an > > optional block ...", a short "WHERE" snippet example showing > this would be > > very helpful. > > > > ------------------------ > > 4.3 Optional Matching > > > > Is there a new syntactic feature introduced here? If so, an > example would be > > helpful. > > ------------------------ > > 5 Nested Patterns > > > > It would be useful to introduce this section with a brief explanation of > > what nesting is. Ie, What is its purpose? Why is it useful? > > > > ------------------------ > > Final example in section: > > > > I don't see a correspondance between the arguments of the > SELECT statement > > and the headings in the result table. "mbox" would have to be > SELECTed to be > > output, wouldn't it, and what happened to "name"? > > > > ------------------------ > > 8 Choosing What to Query > > > > Third paragraph, "To execute a query, there needs to be the > query and an RDF > > graph." > > Awkward. How about: "Query execution requires both a query and an RDF > > graph." > > > > ------------------------- > > 9 Querying the Origin of Statements > > > > I realize you have a footnote on the first sentence saying the > semantics are > > undefined, but how about at least a very loose explanation of > what a SOURCE > > is in the paragraph itself, so the reader at least has a rough idea of > > you're talking about? Maybe the footnote could be reworked and > moved into > > sentence number two? Ie, something like (I'm not claiming this is > > technically accurate): > > > > " ... many RDF data stores augment this with the source of each > statement. > > Source is at present undefined, but is expected to refer in some > > implementation-dependent way to the document of origin, > possibly given by a > > URL." > > > > or some such. > > > > ------------------------ > > 10 Summary of Query Patterns > > > > Does the bullet "disjunction" correspond to the "alternatives" > mentioned in > > "6 More Pattern Matching - Alternatives"? I don't know the ultimate > > dispostion of this section but suggest if it stays and is > mentioned in this > > list, that the terminology be made consistent. > > > > ------------------------ > > 11.2 Constructing an Output Graph > > > > I'm confused by the three boxed snippets. #3 is labelled > "Example" -- are > > the first two NOT examples as well? What distinguishes #3 from > #1 and #2? > > > > Also, #3 has "PREFIX . . . CONSTRUCT". Are the ellipses part of > the syntax?? > > > > -------------------------- > > 11.4 Asking "yes" or "no" questions > > -> 11.4 Asking "Yes" or "No" Questions > > > > I'd also invert sentence #1 and tighten a bit: > > "In order just to test whether a query pattern has a query > solution or not, > > the application can use the ASK form." > > -> > > "Applications can use the ASK form to test whether a query pattern has a > > solution or not." > > > > ------------------------------ > > 12.1 Standard Operations > > > > "The SPARQL language provides some of the operations on plain > literals, XSD > > integers and XSD floats taken from those in XQuery and XPath > Functions and > > Operators <http://www.w3.org/TR/xpath-functions/>." > > > > A bit awkward. Do you mean: > > > > "The SPARQL language provides a subset of the operations on > plain literals, > > XSD integers and XSD floats defined in XQuery and XPath Functions and > > Operators <http://www.w3.org/TR/xpath-functions/>." > > > > > > -- > -eric > > office: +81.466.49.1170 W3C, Keio Research Institute at SFC, > Shonan Fujisawa Campus, Keio University, > 5322 Endo, Fujisawa, Kanagawa 252-8520 > JAPAN > +1.617.258.5741 NE43-344, MIT, Cambridge, MA 02144 USA > cell: +1.857.222.5741 (does not work in Asia) > > (eric@w3.org) > Feel free to forward this message to any list for any purpose other than > email address distribution. >
Received on Wednesday, 6 October 2004 15:55:58 UTC