- From: Eric Prud'hommeaux <eric@w3.org>
- Date: Sun, 10 Oct 2004 09:03:38 -0400
- To: "Seaborne, Andy" <andy.seaborne@hp.com>
- Cc: Simon Raboczi <raboczi@tucanatech.com>, public-rdf-dawg@w3.org
- Message-ID: <20041010130338.GC2460@w3.org>
On Fri, Oct 08, 2004 at 05:37:17PM +0100, Seaborne, Andy wrote: > > Simon, > > Thanks for the comments so far. Changes and non-changes described inline. > > I'll carry over these comments when you send further reviewers feedback. > > Andy > > > Simon Raboczi wrote: > > > >On 02/10/2004, at 2:28, Seaborne, Andy wrote: > > > > > >>The SPARQL language doc is ready for review in preparation for the > >>telcon next Tuesday. Version v1.73 (or later) of: > >> > >> http://www.w3.org/2001/sw/DataAccess/rq23/ > > > > > >These are my comments on revision 1.97. I'm only up to section 2.2 so > >far, so I have to apologize that it's going to be later coming in than > >I estimated. However, all my comments are on very minor issues. I > >have yet to encounter an issue that would disincline me to endorse the > >document for publication. > > > >=== > > > >[[ 1.97 -- Introduction > >SPARQL is a query language for accessing such RDF graphs. It provides > >facilities to: > > * select information > > * extract RDF subgraphs > > * construct new RDF graphs based on information from the target of the > >query. > >]] > > > >"Select information" seems a trifle vague. > > No change for now. See below. > > > > >[[ 1.97 -- 2 Making Simple Queries > >Patterns are descriptions of graphs with named variables in place of > >some of the graph labels or relationships; the simplest graph patterns > >are single triple patterns. The graph labels are values as defined in > >[RDF Core concepts] and are URIs, plain literals and typed literals. > >Patterns can be combined using various operators into more complicated > >patterns. > >]] > > > >I think it'd be more consistent to call these "graph patterns" rather > >than "patterns". > > v1.103: > Done. > > > > >This is my attempt to kill two birds with one stone, by pushing the > >definition of /graph label/ into 1 Introduction: > > Graph labels considered harmful : see : > > http://lists.w3.org/Archives/Public/public-rdf-dawg/2004OctDec/0054.html > > This section has been updated based on Pat's comments. > > > > >[[ suggestion -- 1 Introduction > >The subject, object and relationship components of graph statements may > >be labeled. The /graph labels/ are values as defined in [RDF Core > >concepts] and are URIs, plain literals or typed literals. > > > >SPARQL is a query language for accessing such RDF graphs. It provides > >facilities to: > > * select labeled components from a target graph > > * extract RDF subgraphs > > * construct new RDF graphs based on information from the target of the > >query. > >]] > > > >[[ suggestion -- 2 Making Simple Queries > >/Graph patterns/ are descriptions of graphs with named variables in > >place of some of the graph labels. The simplest graph patterns are > >/triple patterns/ describing a single statement. More complicated > >graph patterns are formed using various operators to combine triple > >patterns. > >]] > > > >I use the term "statement" above because it was defined in 1 > >Introduction, whereas "triple" hasn't been defined. > > No change. > Triple is from RDF Concepts. > Use of statement has been eliminated from the document. > > > > >=== > > > >2 Making Simple Queries > > > >The <div style="clear:both;"></div> appearing after the first set of > >example diagrams (triple1, triple2, triplePattern1) doesn't have the > >intended effect under either Safari 1.2.3 or Mozilla Firebird 0.7. The > >first of the three diagrams is pushed up by the text "with result:". > > > >The resources <alice@work.example> and <robt@home.example> aren't valid > >URI references. They should have a scheme part, presumably mailto:. > > Can't change at the moment : I don't have the technology to change the > images. > > For now, better to have the text and images agree even if both wrong, > rather than text right and images different. 1.06: I updated the doc a bit to make sure that all the refs to the data in that picture has "email addr" rather than <email addr>. Dan has requested a starting query wihtout bNodes. Simon doesn't want us to label the bNodes. As soon as I come up with the right graph and pattern, I'll update the pictures, alt text and results. (Monkying around with the pictures now will result in lost work.) I say "right graph" because I'm looking for a graph where the graph pattern is nore than one triple pattern, and will realistically match more than one piece of data. I like foaf 'cause it's popular and we can communicate more effectively if we talk about familiar data. My currect favorite for the graph is still a foaf example where alice knows bob and eve and the query doesn't concearn itself with labeling the bNodes as the text never mentions them. Thoughts? > >The labeling of blank nodes with _:1 and _:2 in both the triple > >diagrams and the "who" column of the result gives the impression that > >the blank nodes have labels. People desperately want to believe this, > >but it's not true and I'm uncomfortable about ever giving anyone an > >excuse to think so, doubly so in a W3C-sanctioned document. Removing > >the _:1 and _:2 labels from the triple diagrams and leaving them in the > >result set would make me happier. I prefer "harder to understand" over > >"easy to misunderstand". Nack (for right now) but working on it. > >I would prefer the diagram "query1" to be called "graphPattern1". > > I'll leave this to Eric. 1.06: done > >It would be helpful to make some sort of explanation of the tabular > >result format the first time it occurs. Something along the lines of > >"there is a column for every variable occurring in the graph pattern, a > >row for each solution; a graph label appearing in a column (variable) > >and row (solution) is the value bound to that variable in that > >solution". > > > >=== > > > >2.1 Writing a Simple Query > > > >The data for the first example query should be specified to be in > >N-Triples format. (It wouldn't hurt to similarly label the query as > >being actual SPARQL.) > > No change for publication. > I wanted to get into the example without lots of defining and padding text. > There is some explanation after the example. > > > > >=== > > > >[[ 1.93 -- 2.1 Writing a Simple Query > >... the '?' does not form part of the variables name. > >]] > > > >"variables" should be "variable's" > > v 1.103: > Change made: "variables'" as the first use in the sentence is "Variables". > > I see a panda :-) > > > > >=== > > > >[[ 1.93 -- 2.1 Writing a Simple Query > >The terms quoted by "<>" are.... > >...also possible to write floating point doubles directly. > >]] > > > >I'd be inclined to pare this back to the absolute minimum to explain > >the preceding example, rather than trying to be a synopsis of the next > >several following paragraphs. > > We have duplication between intro 2. and 2.1. Not enough time to fix > before first WD publication. > > > > >[[ suggestion -- 2.1 Writing a Simple Query > ><http://example.org/book/book1> and > ><http://purl.org/dc/elements/1.1/title> are RDF URI references. > >"SPARQL Tutorial" is a plain literal. ?title is a named variable. > >]] > > > >I'd then add a sentence about the format of URI references to the > >beginning of the paragraph about abbreviating them as QNames, and a > >paragraph describing the format of plain literals just before the one > >about typed literals. > > > >[[ suggestion -- 2.1 Writing a Simple Query > >URI References are quoted within angled brackets in the same manner as > >in N-Triples. Because URIRefs can become long, SPARQL provides an > >abbreviation mechanism.... > >]] > > No change. <> for URIs is mentioned in RFC 2396 so it is much wider than > N-triples. > > > > >[[ suggestion -- 2.1 Writing a Simple Query > >Plain literals are quoted within double quotes (") in the manner of > >N-Triples, using a backslash (\) to escape quotation marks and certain > >other characters. As in N-Triples, plain literals may bear an optional > >language tag suffix introduced with '@'. > > > >RDF has typed literals. Such literals are written using "^^".... > >]] > > There is (or will be) a reference to the formats mentioned. Where they do > the "usual" thing, I'd like to keep this doc simple and not explicitly > mention it. > > Also, "Plain literals are quoted within double quotes" needs to apply to > typed and tagged literals as well. > > > > >=== > > > >[[ 1.93 -- 2.1 Writing a Simple Query > >PRFEIX : <http://example.org/book/> > >]] > > > >"PRFEIX" should be "PREFIX" > > v1.103: > Done *2 > > > > >=== > > > >[[ 1.93 -- 2.1 Writing a Simple Query > >Prefixes are syntactic... > >... This query is equivalent to the previous one and will therefor have > >the same results: > > > >PREFIX dcore: <http://purl.org/dc/elements/1.1/> > >PRFEIX xsd: <http://www.w3.org/2001/XMLSchema#> > >]] > > > >"therefor" should be "therefore" > > ~v1.10: changed that text to: > "will give the same results when applied to the same graph." to avoid "same > as" discussions. > > > > >"PRFEIX" should be "PREFIX" > > v1.103: > Done > > > > >=== > > > >(Continue with 2.2 and further tomorrow.) > > > > > -- -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 Sunday, 10 October 2004 13:03:39 UTC