– DRAFT –
RDF & SPARQL WG, SPARQL Task Force

<james> i just received a phone call, that my apartment is flooded. it will take a few minutes

<AndyS> Thank you Ted!

<AndyS> SQL correlation example

<AndyS> w3c/sparql-query#156 (comment)

<gb> Issue 156 Addressing SPARQL EXISTS errata (by afs) [ErratumRaised]

<AndyS> pfps examples (from today)

<AndyS> This one -- FILTER EXISTS { FILTER ( ?z = 7 ) } -- is section 8.3.3 in the spec - and is one.

<AndyS> https://www.sparql.org/sparql.html

<AndyS> EXISTS { SELECT ?k WHERE { SELECT ?z1 WHERE { FILTER ( ?z1 = 7 ) } }

<pfps> Here is the problem: substitute(pattern, μ) = the pattern formed by replacing every occurrence of a variable v in pattern by μ(v) for each v in dom(μ)

<pfps> There is no v there

<pfps> sorry, no problem

<gtw> still a problem. just garbled noise.

<pfps> I spoke again, but I guess you didn't hear me. I don't know what the problem is.

<pfps> it seems like there are multiple problems

<pfps> I'm goint to reconnect

<pfps> I have audio now

<AndyS> https://www.w3.org/TR/sparql12-query/#variableScope

<james> wrt #variableScope, the concern is the consequence of those rules for "substitution", rather than in general. while the simplest model would be that the "same" rules apply, that may be hard to understand.

<AndyS> https://github.com/w3c/rdf-star-wg/wiki/SPARQL-Task-Force

<AndyS> FILTER EXISTS { SELECT ?z WHERE { FILTER ( ?z = 7 ) } }

<james> the third in th elist ins

<james> PREFIX ex: <https://example.com/>

<james> SELECT ?x ?y ?z WHERE {

<james> VALUES (?x ?y ?z) { ( ex:a ex:b 7 ) }

<james> { SELECT ?z WHERE { FILTER ( ?z = 7 ) } }

<james> }

<AndyS> VALUES ... FILTER EXISTS { FILTER ( ?z = 7 ) } and VALUES ...join... { FILTER ( ?z = 7 ) }

<pfps> Similarly { FILTER ( ?z = 7 ) } versus FILTER EXISTS { { FILTER ( ?z = 7 ) } }

<AndyS> VALUES ...join... { FILTER ( ?z = 7 ) } and VALUES ...FILTER ( ?z = 7 ) are different anyway