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examples.mdwn

I’m going to try improving Naya and detecting problems by taking the [[sparql-examples]] list and translating the examples one by one to Naya.

• Query structure: q = (P, A, V, K, T, H, l, N)
• Default/no value marker: -
• Empty set marker: /
• uid placeholders: <&x>, <&y>, etc.
• Parameter prefix: $
• Optional parameter prefix: %
• Variable prefix: ?

2.1

[[!format n3 """ SELECT ?title WHERE { http://example.org/book/book1 http://purl.org/dc/elements/1.1/title ?title . } """]]

• P = $title
• A = /
• V = ?i
• K = <&book> <&title>
• T = (?i <&book> <&title> $title)
• H = /
• l = -
• N = /

2.2

[[!format n3 """ PREFIX foaf: http://xmlns.com/foaf/0.1/ SELECT ?name ?mbox WHERE { ?x foaf:name ?name . ?x foaf:mbox ?mbox } """]]

• P = $name $mbox
• A = /
• V = ?i ?j ?x
• K = /
• T = AND{(?i ?x foaf:name $name), (?j ?x foaf:mbox $mbox)}
• H = /
• l = en
• N = foaf:<&foaf>

2.3.1

[[!format n3 """ SELECT ?v WHERE { ?v ?p "cat"@en } """]]

• P = $v
• A = /
• V = ?i ?p
• K = /
• T = (?i $v ?p “cat”)
• H = /
• l = -
• N = /

Or:

• P = $v
• A = /
• V = ?i ?j ?k ?p ?text
• K = <&lang> <&content> <&en>
• T = AND{(?i $v ?p ?text), (?j ?text <&lang> <&en>), (?k ?text <&content> “cat”)}
• H = /
• l = -
• N = /

2.3.2

[[!format n3 """ SELECT ?v WHERE { ?v ?p 42 } """]]

• P = $v
• A = /
• V = ?i ?p
• K = /
• T = (?i $v ?p 42)
• H = /
• l = -
• N = /

2.3.3

[[!format n3 """ SELECT ?v WHERE { ?v ?p “abc”^^http://example.org/datatype#specialDatatype } """]]

• P = $v
• A = /
• V = ?i ?p
• K = /
• T = (?i $v ?p “abc”@<&dt>)
• H = /
• l = -
• N = /

2.4

?

2.5

These are two queries, but they mean exactly the same thing.

[[!format n3 """ PREFIX foaf: http://xmlns.com/foaf/0.1/ SELECT ( CONCAT(?G, " ", ?S) AS ?name ) WHERE { ?P foaf:givenName ?G ; foaf:surname ?S }

PREFIX foaf: http://xmlns.com/foaf/0.1/ SELECT ?name WHERE { ?P foaf:givenName ?G ; foaf:surname ?S BIND(CONCAT(?G, " “, ?S) AS ?name) }”""]]

• P = $name
• A = /
• V = ?i ?j ?P ?G ?S
• K = /
• T = AND{(?i ?P foaf:givenName ?G), (?j ?P foaf:surname ?S), ($name = concat(?G, " ", ?S))}
• H = /
• l = en
• N = foaf:<&foaf>

2.6

[[!format n3 """ PREFIX foaf: http://xmlns.com/foaf/0.1/ PREFIX org: http://example.com/ns#

CONSTRUCT { ?x foaf:name ?name } WHERE { ?x org:employeeName ?name } """]]

• P = ($x foaf:name $name)
• A = /
• V = ?i
• K = /
• T = (?i $x world:personName $name)
• H = /
• l = en
• N = foaf:<&foaf> world:<&world>

3.1

Doing just the first one. The second is the same, but with a case-insensitive regex.

[[!format n3 """ PREFIX dc: http://purl.org/dc/elements/1.1/ SELECT ?title WHERE { ?x dc:title ?title FILTER regex(?title, “^SPARQL”) }

PREFIX dc: http://purl.org/dc/elements/1.1/ SELECT ?title WHERE { ?x dc:title ?title FILTER regex(?title, “web”, “i” ) } """]]

• P = ($title)
• A = /
• V = ?i ?x
• K = <&matches_regex>
• T = AND{(?i ?x dc:title title), (title <&matches_regex> “^SPARQL”)}
• H = /
• l = en
• N = dc:<&dc>

3.2

[[!format n3 """ PREFIX dc: http://purl.org/dc/elements/1.1/ PREFIX ns: http://example.org/ns# SELECT ?title ?price WHERE { ?x ns:price ?price . FILTER (?price < 30.5) ?x dc:title ?title . } """]]

• P = ($title, $size)
• A = /
• V = ?i ?j ?x
• K = /
• T = AND{(?i ?x ns:size size), (size < 30.5), (?j ?x dc:title $title)}
• H = /
• l = en
• N = dc:<&dc> ns:<&ns>

4.2.3

[[!format n3 """ (1 ?x 3 4) :p “w” .

(1 [:p :q] ( 2 ) ) . """]]

This is just syntactic sugar for RDF collections, but these are simply encoded in triples so no new model features are introduced by them.

6.1

[[!format n3 """ PREFIX foaf: http://xmlns.com/foaf/0.1/ SELECT ?name ?mbox WHERE { ?x foaf:name ?name . OPTIONAL { ?x foaf:mbox ?mbox } } """]]

• P = $name
• A = %mbox
• R = ($name %mbox)
• V = ?i ?j ?x
• K = /
• T = AND{(?i ?x foaf:name $name), (?j ?x foaf:mbox %mbox)}
• H = /
• l = en
• N = foaf:<&foaf>

6.2

[[!format n3 """ PREFIX dc: http://purl.org/dc/elements/1.1/ PREFIX ns: http://example.org/ns# SELECT ?title ?price WHERE { ?x dc:title ?title . OPTIONAL { ?x ns:price ?price . FILTER (?price < 30) } } """]]

• P = $title
• A = %size
• R = ($title %size)
• V = ?i ?j ?x
• K = /
• T = AND{(?i ?x dc:title $title), (?j ?x ns:size %size), (%size < 30)}
• H = /
• l = en
• N = dc:<&dc> ns:<&ns>

6.3

[[!format n3 """ PREFIX foaf: http://xmlns.com/foaf/0.1/ SELECT ?name ?mbox ?hpage WHERE { ?x foaf:name ?name . OPTIONAL { ?x foaf:mbox ?mbox } . OPTIONAL { ?x foaf:homepage ?hpage } } """]]

• P = $name
• A = %mbox %hpage
• R = ($name %mbox %hpage)
• V = ?i ?j ?k ?x
• K = /
• T = AND{(?i ?x foaf:name $name), (?j ?x foaf:mbox %mbox), (?k ?x foaf:homepage %hpage)}
• H = /
• l = en
• N = foaf:<&foaf>

7

[[!format n3 """ PREFIX dc10: http://purl.org/dc/elements/1.0/ PREFIX dc11: http://purl.org/dc/elements/1.1/ SELECT ?title WHERE { { ?book dc10:title ?title } UNION { ?book dc11:title ?title } }

PREFIX dc10: http://purl.org/dc/elements/1.0/ PREFIX dc11: http://purl.org/dc/elements/1.1/ SELECT ?x ?y WHERE { { ?book dc10:title ?x } UNION { ?book dc11:title ?y } }

PREFIX dc10: http://purl.org/dc/elements/1.0/ PREFIX dc11: http://purl.org/dc/elements/1.1/ SELECT ?title ?author WHERE { { ?book dc10:title ?title . ?book dc10:creator ?author } UNION { ?book dc11:title ?title . ?book dc11:creator ?author } } """]]

• P = $title
• A = /
• R = ($title)
• V = ?i ?book
• K = /
• T = OR{(?i ?book dc10:title $title), (?i ?book dc11:title $title)}
• H = /
• l = en

• N = dc10:<&dc10> dc11:<&dc11>

• P = /
• A = %x %y
• R = (%x %y)
• V = ?i ?book
• K = /
• T = AND{(?i ?book dc10:title %x), (?i ?book dc11:title %y)}
• H = /
• l = en

• N = dc10:<&dc10> dc11:<&dc11>

• P = $title $author
• A = /
• R = ($title $author)
• V = ?i ?j ?book
• K = /
• T = OR{ AND{(?i ?book dc10:title $title), (?j ?book dc10:creator $author)}, AND{(?i ?book dc11:title $title), (?j ?book dc11:creator $author)} }
• H = /
• l = en

• N = dc10:<&dc10> dc11:<&dc11>

8.1.1

[[!format n3 """ PREFIX rdf: http://www.w3.org/1999/02/22-rdf-syntax-ns# PREFIX foaf: http://xmlns.com/foaf/0.1/

SELECT ?person WHERE { ?person rdf:type foaf:Person . FILTER NOT EXISTS { ?person foaf:name ?name } } """]]

Discussed in [[design3]].

8.1.2

[[!format n3 """ PREFIX rdf: http://www.w3.org/1999/02/22-rdf-syntax-ns# PREFIX foaf: http://xmlns.com/foaf/0.1/

SELECT ?person WHERE { ?person rdf:type foaf:Person . FILTER EXISTS { ?person foaf:name ?name } } """]]

Discussed in [[design3]].

8.2

[[!format n3 """ PREFIX : http://example/ PREFIX foaf: http://xmlns.com/foaf/0.1/

SELECT DISTINCT ?s WHERE { ?s ?p ?o . MINUS { ?s foaf:givenName “Bob” . } } """]]

“Distinct” is trivial to specify. “Minus” can be modeled using other things in this case, but let’s check the SPARQL spec and see how it works. Hmmm… yes, it looks like I can do the same with other features I already have. I’m adding a distinct flag.

• P = $s
• A = /
• R = ($s)
• V = ?i ?p ?o
• K = /
• T = AND{(?i $s ?p ?o), OR{(?p != foaf:givenName), (?o != “Bob”)}}
• H = /
• l = en
• N = foaf:<&foaf>
• d = true

8.3.1

[[!format n3 """ SELECT * { ?s ?p ?o FILTER NOT EXISTS { ?x ?y ?z } }

SELECT * { ?s ?p ?o MINUS { ?x ?y ?z } } """]]

• P = $s $p $o
• A = /
• R = ($s $p $o)
• V = ?i
• W = ^j ^x ^y ^z
• K = /
• T = AND{(?i $s $p $o), (^j ^x ^y ^z)}
• H = /
• l = -
• N = /
• d = false

8.3.2

TODO continue here after design 4

[[TODO|TODO/OPEN]] continue here to next example