- From: Lee Feigenbaum <lee@thefigtrees.net>
- Date: Mon, 11 Jan 2010 13:33:11 -0500
- To: matthew.perry@oracle.com
- CC: W3C SPARQL Working Group <public-rdf-dawg@w3.org>
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 Are the Plain SQL set simply the set that can be expanded as a (possibly complicated) SPARQL 1.0 query string? (This is sort of but not exactly what's termed a "simple path" in the current doc.) Do other DBMSes included equivalent/similar functionality to CONNECT BY? I'm hesitant to go down a multi-level conformance path in the first place, but I'd be even more hesitant to do so if it were just in the context of a single DBMS. Lee > > Thanks, > Matt > > > >
Received on Monday, 11 January 2010 18:33:48 UTC