- From: Andy Seaborne <andy.seaborne@talis.com>
- Date: Tue, 12 Jan 2010 09:03:13 +0000
- To: matthew.perry@oracle.com
- CC: Ivan Herman <ivan@w3.org>, W3C SPARQL Working Group <public-rdf-dawg@w3.org>
I don't understand the restriction to one unbounded path component. Looking at: { :v1 :myProp1*/:myProp2+/:myProp3? :v2 } It is the same as: { :v1 :myProp1* ?x1 . ?x2 :myProp2+ ?x3 . ?x3 :myProp3? :v2 } Matt - What is the key difference between the supported and unsupported examples? Andy On 11/01/2010 7:12 PM, Matt Perry wrote: > Hi Ivan, > > Basically, combinations of complex paths are not supported. > > For example, { :v1 :myProp1* :v2 }, { :v1 :myProp2+ :v2 }, and { :v1 > :myProp3? :v2 } are all supported, but { :v1 > :myProp1*/:myProp2+/:myProp3? :v2 } is not supported. > > Hope this helps, > -Matt > > Ivan Herman wrote: >> Matt, >> >> to make things more understandable (for me:-) can you summarize what are >> the features in the current property path document[1] that are _not_ >> covered? Ie, what do we give up if we use such profile(s)? >> >> Thanks for your help >> >> Ivan >> >> [1]http://www.w3.org/2009/sparql/docs/property-paths/Overview.xml >> >> On 2010-1-11 19:25 , Matt Perry wrote: >> >>> Hi, >>> >>> During the last TC, I mentioned the possibility of a Property Paths >>> profile that identifies a subset of property path queries that can be >>> expressed with SQL. Such a profile would make it easy for triple stores >>> implemented on top of relational databases to identify the set of >>> property path queries that they "natively" support. The purpose of this >>> email is to start a discussion about the possibility of property path >>> profiles. >>> >>> The grammars below show two possible fragments that we have identified. >>> The first grammar is for SQL + CONNECT BY (Oracle) and the second is for >>> PLAIN SQL. >>> >>> CONNECT BY: >>> >>> ALT -> URI | URI|ALT >>> SEQ -> URI | URI/SEQ >>> Elem -> URI | SEQ | ALT | ^URI >>> COMP -> URI | Elem* | Elem+ | Elem{n,m} | Elem? >>> TOP -> URI | COMP | ALT | SEQ | ^URI >>> >>> PLAIN SQL: >>> >>> ALT -> URI | URI|ALT >>> SEQ -> URI | URI/SEQ >>> Elem -> URI | SEQ | ALT | ^URI >>> COMP -> URI | Elem{n,m} | Elem? >>> TOP -> URI | COMP | ALT | SEQ | ^URI >>> >>> Thanks, >>> Matt >>> >>> >>> >>> >> >> > > > ______________________________________________________________________ > This email has been scanned by the MessageLabs Email Security System. > For more information please visit http://www.messagelabs.com/email > ______________________________________________________________________
Received on Tuesday, 12 January 2010 09:03:52 UTC