The document discusses the ongoing developments and considerations in the SPARQL 1.1 specifications as of May 2010, including new query and update features and service description mechanisms. It highlights the deliberations within the SPARQL working group on various technical questions, such as aggregates, subqueries, and federated queries. Additionally, it invites public engagement and feedback on the SPARQL specifications and mentions the need for a formal update protocol and expanded functionality.

1. 1.1What’s coming and what might be coming?May, 2010Latest at http://www.slideshare.net/LeeFeigenbaum/sparql2-statusLee Feigenbaum, Co-chair, SPARQL Working Grouplee@thefigtrees.net

2. DisclaimerThe SPARQL Working Group has not yet decided many of the technical questions surveyed in these slides. All examples are subject to change; please do not construe them as indicators or endorsements of specific technical designs/decisions.All opinions are Lee Feigenbaum’s alone.

3. NamingSPARQL 1.1 is the collective name of the work produced by the current SPARQL Working Group. The actual components being worked on are known as:SPARQL 1.1 QuerySPARQL 1.1 UpdateSPARQL 1.1 Service Description…

4. Where are we now?TodayAugust 2010March 2009???Last Call and beyond of core SPARQL specificationsJuly 2009FPWD of SPARQL New Features and Rationales documentOctober 2009FPWD of core SPARQL specifications

5. Overview

6. Projected ExpressionsSelect expressions other than variables (literals, functions on literals and variables, etc.)SELECT (?price* ?qty AS ?total_price)WHERE { …}

7. AggregatesÀ la SQL aggregates (MIN, MAX, COUNT, AVG, SUM etc.)Issues around:Aggregates and error valuesGrouping by expressionsSELECT (MIN(?price) AS ?min_price)…WHERE { … }GROUP BY ?item

8. SubqueriesNested queries allow multiple queries to be combined into one. SELECT ?article ?authorWHERE { ?article ex:author ?author . { SELECT ?article WHERE { … ?article … } ORDER BY … LIMIT … }}

9. NegationSupplant the mystifying OPTIONAL/!bound method of negation with a dedicated constructIssues around:Filter semantics vs. set-difference semanticsGraph pattern operators vs. filter functionsSELECT … WHERE { ?person a foaf:Person .MINUS{ ?person foaf:mbox ?email }}

10. Service DescriptionA standard discovery mechanism and vocabulary for describing the capabilities, extensions, data sets, and more for a SPARQL endpointDiscovery. How can a client find the RDF that describes a SPARQL endpoint at a particular URI?Description. What predicates, classes, values, etc. should a client expect to find (and be able to query) once it locates a service description?

11. Update LanguageBased on the SPARQL Update member submissionBatch insert & deleteInsert & delete based on triple patternsGraph management (creation, removal)Issues around:Defining a formal model for updateGraph stores vs. RDF data setsReturn codes

12. Update ProtocolThe ability to issue SPARQL/Update language statements via a standard protocol (e.g. via HTTP POST)Issues around: Security Response HTTP codes

13. HTTP RDF update (RESTful)Where appropriate, map HTTP requests to SPARQL/Update operationsDELETE /foo/g1 …-> DELETE DATA FROM ex:g1 …Issues around:Which mappings to include?Are graphs information resources?

14. Property PathsSupport arbitrary-length predicate paths in triple patterns – “regular expressions” on predicates?Query hierarchical structures such as RDF collectionsIssues around:Duplicates and cycles in pathsNegated path segmentsSELECT … WHERE { ?person foaf:knows+ ?network .}

15. Basic Federated QueryInitial scaffolding for authoring federated SPARQL queriesAdd a keyword to explicitly target portions of a query to specific endpointsIssues around:SERVICE and variables?Is federated query its own document?SELECT … WHERE { … SERVICE ex:books { … }}

16. Entailment Regime SemanticsSPARQL/Query 1.0 defines a mechanism to extend SPARQL semantics for additional entailment regimesUse this mechanism to define the semantics of SPARQL queries for:RDF SchemaOWL fragmentsRIF rule sets…

17. Common FunctionsExtend the set of functions that SPARQL engines must support to include some of…Common string functions (e.g. substr)Common date/time/datetime functionsLogical functions (COALESCE, IF, …?)Limited discussion to date about which functions to include

18. Get InvolvedJoin. Email team-sparql-chairs@w3.orgFollow. WG materials at http://www.w3.org/2009/sparql/wiki/Comment. Public feedback at public-rdf-dawg-comments@w3.orgUse. Discuss SPARQL at public-sparql-dev@w3.org