- From: Steve Harris <steve.harris@garlik.com>
- Date: Mon, 29 Mar 2010 16:13:19 +0100
- To: Andy Seaborne <andy.seaborne@talis.com>
- Cc: Eric Prud'hommeaux <eric@w3.org>, public-rdf-dawg@w3.org
+1 - Steve On 29 Mar 2010, at 15:54, Andy Seaborne wrote: > Eric, > > This is great - I think we ought to include something in SPARQL 1.1 > even if it's just the most basic SERVICE form because of time. It > it the semantic *web* .... > > Andy > > On 27/03/2010 3:36 AM, Eric Prud'hommeaux wrote: >> http://www.w3.org/2009/sparql/docs/fed/service >> >> take a look, help out, ... >> -- >> -ericP > > > Specific comments: > ** SERVICE > > "4.1 Definition of SERVICE" > http://www.w3.org/2009/sparql/docs/fed/service#sparqlDefinition > > [[ > The evaluation of service uses the SPARQL algebra union operator. > ]] > > Elements of a group are usually join'ed together, not union'ed. > > Algebra example: > > Service(?s :p2 ?v2) > ==> > Service(<srvc> BGP(?s :p2 ?v2)) > > "with a query Q and no default or named graphs." > > I think that means no FROM or FROM NAMED - correct? > > > ** BINDINGS > > This area is less clear to me - it's very useful to have something > here but I'm not quite sure this is the right mechanism. > > It's another form of assignment. > > Is it the same as (the excessively verbose): > > { > SELECT ("Alice" AS ?given) > ("Anderson" AS ?family) > (?mbox AS <mailto:alice@example.com>) > } UNION { > SELECT ("Bob" AS ?given) > ("Robertson" AS ?family) > (?mbox AS <mailto:eve@example.com>) > } UION { ... } > > > Probably better not to allow bNodes to be passed over the network. > > Suggest s/UNBOUND/_/ or something a liitle less heavy. "-" > The definition of BINDING has UNDEF > > > * BINDING and Update: > This seems to overlap with INSERT DATA etc > It is unrelated to federated query. > > The substutute operator might help in the definition: > http://www.w3.org/2009/sparql/docs/query-1.1/rq25.xml#defn_substitute > > Result are then a union of substitute for each binding row. This is > similar to the bind-join proposed by the IBM Garlic project. It > allows for the bINDINGs to be streamed in parallel with results > coming back. > > (this way the results of sending one BINDING at a time and sending > all BINDINGS at once are the same). > > ** MIME Type > > Doesn't the query often go in ?query= which isn't MIME typed. > > Andy > -- Steve Harris, Garlik Limited 2 Sheen Road, Richmond, TW9 1AE, UK +44 20 8973 2465 http://www.garlik.com/ Registered in England and Wales 535 7233 VAT # 849 0517 11 Registered office: Thames House, Portsmouth Road, Esher, Surrey, KT10 9AD
Received on Monday, 29 March 2010 15:13:50 UTC