3. Agenda
1. Introduc+on
to
SPARQL
2. Querying
Linked
Data
with
SPARQL
3. SPARQL
Algebra
4. Upda+ng
Linked
Data
with
SPARQL
1.1
5. SPARQL
Protocol
6. Reasoning
over
Linked
Data
EUCLID
-‐
Querying
Linked
Data
3
5. SPARQL
Seman6c
Web
Stack
Berners-‐Lee
(2006)
*
Protocol
and
RDF
Query
Language
EUCLID
-‐
Querying
Linked
Data
5
Declara6ve
query
language
6. SPARQL
EUCLID
-‐
Querying
Linked
Data
6
• SPARQL
Query
– Declara6ve
query
language
for
RDF
data
– hp://www.w3.org/TR/rdf-‐sparql-‐query/
• SPARQL
Algebra
– Standard
for
communica6on
between
SPARQL
services
and
clients
– hp://www.w3.org/2001/sw/DataAccess/rq23/rq24-‐algebra.html
• SPARQL
Update
– Declara6ve
manipula6on
language
for
RDF
data
– hp://www.w3.org/TR/sparql11-‐update/
• SPARQL
Protocol
– Standard
for
communica6on
between
SPARQL
services
and
clients
– hp://www.w3.org/TR/sparql11-‐protocol/
7. SPARQL
Query
1.1
• Aggregates,
Subqueries,
Nega6on,
Expressions
in
the
SELECT
clause,
Property
paths,
assignment,
short
form
for
CONSTRUCT,
expanded
set
of
func6ons
and
operators
EUCLID
-‐
Querying
Linked
Data
7
• SPARQL
1.0
only
allows
accessing
the
data
(query)
• SPARQL
1.1
introduces:
Query
extensions
Updates
• Data
management:
Insert,
Delete,
Delete/Insert
• Graph
management:
Create,
Load,
Clear,
Drop,
Copy,
Move,
Add
Federa6on
extension
• Service,
values,
service
variables
(informa6ve)
CH
5
8. SPARQL
Basics
dbpedia:The_Beatles
foaf:name
"The
Beatles"
.
dbpedia:The_Beatles
foaf:made
?album.
?album
mo:track
?track
.
?album
?p
?o
.
EUCLID
-‐
Querying
Linked
Data
8
• RDF
triple:
Basic
building
block,
of
the
form
subject,
predicate,
object.
Example:
• RDF
triple
paNern:
Contains
one
or
more
variables.
Examples:
• RDF
quad
paNern:
Contains
graph
name:
URI
or
variable.
Examples:
GRAPH
<:g>
{:s
:p
:o
.}
GRAPH
?g
{dbpedia:The_Beatles
foaf:name
?o.}
9. SPARQL
Basics
EUCLID
-‐
Querying
Linked
Data
9
• RDF
graph:
Set
of
RDF
asser6ons,
manipulated
as
a
labeled
directed
graph.
• RDF
data
set:
set
of
RDF
triples.
It
is
comprised
of:
• One
default
graph
• Zero
or
more
named
graphs
• SPARQL
protocol
client:
HTTP
client
that
sends
requests
for
SPARQL
Protocol
opera6ons
(queries
or
updates)
• SPARQL
protocol
service:
HTTP
server
that
services
requests
for
SPARQL
Protocol
opera6ons
• SPARQL
endpoint:
The
URI
at
which
a
SPARQL
Protocol
service
listens
for
requests
from
SPARQL
clients
11. SPARQL
Query
EUCLID
-‐
Querying
Linked
Data
11
Main
idea:
PaNern
matching
• Queries
describe
sub-‐graphs
of
the
queried
graph
• Graph
paNerns
are
RDF
graphs
specified
in
Turtle
syntax,
which
contain
variables
(prefixed
by
either
“?”
or
“$”)
• Sub-‐graphs
that
match
the
graph
paerns
yield
a
result
dbpedia:
?album
The_Beatles
foaf:made
15. SPARQL
Query:
Components
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
PREFIX
mo:
<http://purl.org/ontology/mo/>
SELECT
?album
FROM
<http://musicbrainz.org/20130302>
WHERE
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
a
mo:Record
;
dc:title
?title
EUCLID
-‐
Querying
Linked
Data
15
}
ORDER
BY
?title
Prologue:
•
Prefix
defini6ons
•
Subtly
different
from
Turtle
syntax
-‐
the
final
period
is
not
used
16. SPARQL
Query:
Components
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
PREFIX
mo:
<http://purl.org/ontology/mo/>
SELECT
?album
FROM
<http://musicbrainz.org/20130302>
WHERE
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
a
mo:Record
;
dc:title
?title
EUCLID
-‐
Querying
Linked
Data
16
}
ORDER
BY
?title
Query
form:
• ASK,
SELECT,
DESCRIBE
or
CONSTRUCT
• SELECT
retrieves
variables
and
their
bindings
as
a
table
17. SPARQL
Query:
Components
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
PREFIX
mo:
<http://purl.org/ontology/mo/>
SELECT
?album
FROM
<http://musicbrainz.org/20130302>
WHERE
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
a
mo:Record
;
dc:title
?title
EUCLID
-‐
Querying
Linked
Data
17
}
ORDER
BY
?title
Data
set
specifica+on:
• This
clause
is
op6onal
• FROM
or
FROM
NAMED
• Indicates
the
sources
for
the
data
against
which
to
find
matches
18. SPARQL
Query:
Components
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
PREFIX
mo:
<http://purl.org/ontology/mo/>
SELECT
?album
FROM
<http://musicbrainz.org/20130302>
WHERE
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
a
mo:Record
;
dc:title
?title
EUCLID
-‐
Querying
Linked
Data
18
}
ORDER
BY
?title
Query
paNern:
• Defines
paerns
to
match
against
the
data
• Generalises
Turtle
with
variables
and
keywords
–
N.B.
final
period
op6onal
19. SPARQL
Query:
Components
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
PREFIX
mo:
<http://purl.org/ontology/mo/>
SELECT
?album
FROM
<http://musicbrainz.org/20130302>
WHERE
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
a
mo:Record
;
dc:title
?title
Solu+on
modifier:
• Modify
the
result
set
• ORDER
BY,
LIMIT
or
OFFSET
re-‐organise
rows;
• GROUP
BY
combines
them
EUCLID
-‐
Querying
Linked
Data
19
}
ORDER
BY
?title
20. Query
Forms
SPARQL
supports
different
query
forms:
• ASK
tests
whether
or
not
a
query
paern
has
a
solu6on.
Returns
yes/no
• SELECT
returns
variables
and
their
bindings
EUCLID
-‐
Querying
Linked
Data
20
directly
• CONSTRUCT
returns
a
single
RDF
graph
specified
by
a
graph
template
• DESCRIBE
returns
a
single
RDF
graph
containing
RDF
data
about
resource
21. Query
Form:
ASK
Is
Paul
McCartney
member
Results:
Results:
EUCLID
-‐
Querying
Linked
Data
21
• Namespaces
are
added
with
the
‘PREFIX’
direc6ve
• Statement
paerns
that
make
up
the
graph
are
specified
between
brackets
(“{}”)
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
dbpedia-‐ont:
<http://dbpedia.org/ontology/>
PREFIX
mo:
http://purl.org/ontology/mo/
ASK
WHERE
{
dbpedia:The_Beatles
mo:member
dbpedia:Paul_McCartney.}
Query:
of
‘The
Beatles’?
true
Query:
Is
Elvis
Presley
member
of
‘The
Beatles’?
false
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
dbpedia-‐ont:
<http://dbpedia.org/ontology/>
PREFIX
mo:
http://purl.org/ontology/mo/
ASK
WHERE
{
dbpedia:The_Beatles
mo:member
dbpedia:Elvis_Presley.}
22. Query
Form:
SELECT
What
albums
and
tracks
did
‘The
Beatles’
make?
EUCLID
-‐
Querying
Linked
Data
22
• The
solu6on
modifier
projec+on
nominates
which
components
of
the
matches
should
be
returned
• “*”
means
all
components
should
be
returned
Query:
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
PREFIX
mo:
<http://purl.org/ontology/mo/>
SELECT
?album_name
?track_title
WHERE
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
dc:title
?album_name
;
mo:track
?track
.
?track
dc:title
?track_title
.}
23. Query
Form:
SELECT
(2)
Filter
expressions
• Different
types
of
filters
and
func6ons
may
be
used
Filter:
Comparison
and
logical
operators
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
PREFIX
mo:
<http://purl.org/ontology/mo/>
SELECT
?album_name
?track_title
?date
?duration
WHERE
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
dc:title
?album_name
;
mo:track
?track
.
?track
dc:title
?track_title
;
mo:duration
?duration;
FILTER
(?duration>300000
&&
?duration<400000)
}
EUCLID
-‐
Querying
Linked
Data
23
Query:
Retrieve
the
albums
and
tracks
recorded
by
‘The
Beatles’,
where
the
duraCon
of
the
song
is
more
than
300
secs.
and
no
longer
than
400
secs.
24. Query
Form:
SELECT
(3)
Elimina+on
of
duplicates
Retrieve
the
name
of
the
albums
recorded
by
‘The
Beatles’
which
have
at
least
Query:
two
different
songs.
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
PREFIX
mo:
<http://purl.org/ontology/mo/>
SELECT
Results:
EUCLID
-‐
Querying
Linked
Data
24
MODIFIER
?album_name
WHERE
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
dc:title
?album_name
.
mo:track
?track1
.
mo:track
?track2
.
FILTER
(?track1
!=
?track2)
}
?album
“Revolver”
“Sessions”
“Abbey
Road”
?album
“Revolver”
“Revolver”
“Revolver”
“Sessions”
“Abbey
Road”
“Abbey
Road”
DISTINCT
REDUCED
MODIFIER=
MODIFIER=
25. Query
Form:
SELECT
(4)
Aggregates
• Calculate
aggregate
values:
COUNT,
SUM,
MIN,
MAX,
AVG,
GROUP_CONCAT
and
SAMPLE
• Built
around
the
GROUP
BY
operator
• Prune
at
group
level
(cf.
FILTER)
using
HAVING
Retrieve
the
duraCon
of
the
albums
recorded
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
mo:
<http://purl.org/ontology/mo/>
SELECT
?album
(SUM(?track_duration)
AS
?album_duration)
WHERE
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
mo:track
?track
.
?track
mo:duration
?track_duration
.
}
GROUP
BY
?album
HAVING
(SUM(?track_duration)
>
3600000)
EUCLID
-‐
Querying
Linked
Data
25
Query:
by
‘The
Beatles’.
26. Query
Form:
DESCRIBE
Takes
the
resources
within
the
solu6on,
and
provides
informa6on
about
them
as
RDF
statements.
They
can
be
iden6fied
by:
• Specifying
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
DESCRIBE
dbpedia:Paul_McCartney
EUCLID
-‐
Querying
Linked
Data
26
explicit
IRIs
• Bindings
of
variables
in
the
WHERE
clause
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
mo:
<http://purl.org/ontology/mo/>
DESCRIBE
?member
WHERE
{
dbpedia:The_Beatles
mo:member
?member
.}
27. Query
Form:
CONSTRUCT
EUCLID
-‐
Querying
Linked
Data
27
• CONSTRUCT
WHERE:
In
order
to
query
for
a
subgraph,
without
change,
it
is
no
longer
necessary
to
repeat
the
graph
paern
in
the
template
Example:
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
mo:
<http://purl.org/ontology/mo/>
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
CONSTRUCT
WHERE
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
mo:track
?track
.}
29. Query
Form:
CONSTRUCT
(2b)
Create
the
dc:creator
descripCons
for
albums
and
their
tracks
recorded
by
‘The
Beatles’.
EUCLID
-‐
Querying
Linked
Data
29
• Returns
RDF
statements
created
from
variable
bindings
• Template:
graph
paern
with
variables
from
the
query
paern
Query:
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
mo:
<http://purl.org/ontology/mo/>
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
CONSTRUCT
{
?album
dc:creator
dbpedia:The_Beatles
.
?track
dc:creator
dbpedia:The_Beatles
.}
WHERE
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
mo:track
?track
.}
30. Query
Form:
CONSTRUCT
(3)
Create
the
dc:creator
descripCons
for
the
10
most
recent
albums
and
their
tracks
recorded
EUCLID
-‐
Querying
Linked
Data
30
Subsets
of
results
• It
is
possible
to
combine
the
query
with
solu+on
modifiers
(ORDER
BY,
LIMIT,
OFFSET)
Query:
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
mo:
<http://purl.org/ontology/mo/>
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
CONSTRUCT
{
?album
dc:creator
dbpedia:The_Beatles
.
?track
dc:creator
dbpedia:The_Beatles
.}
WHERE
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
mo:track
?track
;
dc:date
?date
.
}
ORDER
BY
DESC(?date)
LIMIT
10
by
‘The
Beatles’.
31. Query
Form:
CONSTRUCT
(4)
Union
Graph
PaNern
• Allows
the
specifica6on
of
alterna6ves
(disjunc6ons)
Create
the
dc:creator
descripCons
for
the
albums
recorded
by
‘The
Beatles’
in
‘Abbey
Road
Studios’
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
http://xmlns.com/foaf/0.1/
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
CONSTRUCT
{
?album
dc:creator
dbpedia:The_Beatles
.
?track
dc:creator
dbpedia:The_Beatles
.}
WHERE
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
dc:title
?album_name
.
{?album
dbpedia-‐ont:recordedIn
dbpedia:Abbey_Road_Studios
.}
UNION
{?album
dbpedia-‐ont:recordedIn
dbpedia:Trident_Studios
.}}
EUCLID
-‐
Querying
Linked
Data
31
Query:
or
‘Trident
Studios’
32. Query
Form:
CONSTRUCT
(5)
Filter
expressions
• Different
types
of
filters
and
func6ons
may
be
used
Filter:
Regular
expressions
over
strings
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
CONSTRUCT
{?album
dc:creator
dbpedia:The_Beatles
.}
WHERE
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
dc:title
?album_name
;
FILTER
(REGEX(?album_name,
".*love.*",
i))
}
EUCLID
-‐
Querying
Linked
Data
32
Query:
Create
the
dc:creator
descripCons
of
the
albums
recorded
by
‘The
Beatles’
whose
Ctle
contains
the
word
‘love
.
33. Query
Form:
CONSTRUCT
(6)
Type
of
func+on
Func+on
Result
type
Func6onal
Forms
bound
IF
COALESCE
NOT
EXISTS,
EXISTS
or,
and
RDFTerm-‐equal
(=),
sameTerm
IN,
NOT
IN
xsd:boolean
rdfTerm
rdfTerm
xsd:boolean
xsd:boolean
xsd:boolean
boolean
Func6ons
on
RDF
Terms
isIRI,
isBlank,
isLiteral,
isNumeric
str,
lang,
datatype
IRI
BNODE
xsd:boolean
simple
literal
iri
iri
blank
node
Func6ons
on
Numerics
ABS,
ROUND,
CEIL,
FLOOR
RAND
numeric
xsd:double
Filter
expressions
Source:hp://www.w3.org/TR/sparql11-‐query/#SparqlOps
EUCLID
-‐
Querying
Linked
Data
33
34. Query
Form:
CONSTRUCT
(7)
Type
of
func+on
Func+on
Result
type
Func6ons
on
Strings
STRLEN
SUBSTR,
UCASE,
LCASE
STRSTARTS,
STRENDS,
CONTAINS
STRBEFORE,
STRAFTER
ENCODE_FOR_URI
CONCAT
langMatches
REGEX
REPLACE
xsd:integer
string
literal
xsd:boolean
literal
simple
literal
string
literal
xsd:boolean
xsd:boolean
string
literal
Func6ons
on
Dates
and
Times
now
year,
month,
day,
hours,
minutes
seconds
6mezone
tz
xsd:dateTime
xsd:integer
xsd:decimal
xsd:dayTimeDura6on
simple
literal
Filter
expressions
Source:hp://www.w3.org/TR/sparql11-‐query/#SparqlOps
EUCLID
-‐
Querying
Linked
Data
34
35. Query
Form:
CONSTRUCT
(8)
Op+onal
Graph
PaNern
• OPTIONAL
clause
encloses
the
op6onal
parts
• If
variables
in
the
construct
clause
are
not
bound
in
the
op6onal,
the
triple
paerns
with
these
variables
are
not
generated
Create
the
dc:creator
and
dc:depicts
descripQuery:
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
PREFIX
dbpedia-‐owl:
<http://dbpedia.org/ontology/>
CONSTRUCT
{
?album
dc:creator
?artist
.
?picture
dc:depicts
?artist
.
}
EUCLID
-‐
Querying
Linked
Data
35
WHERE
{
?artist
foaf:made
?album
.
OPTIONAL
{?artist
foaf:depiction
?picture
.}}
Cons
of
arCsts.
36. Query
Form:
CONSTRUCT
(9)
Op+onal
Graph
PaNern
• Can
test
if
variables
are
bound
in
filter
expressions
• Solu6ons
that
meet
the
OPTIONAL
clause
can
be
filtered
out
by
using
the
logical
filter
NOT
(!)
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
PREFIX
dbpedia-‐owl:
<http://dbpedia.org/ontology/>
CONSTRUCT
{
?album
dc:creator
?artist
.
}
WHERE
{
?artist
foaf:made
?album
.
OPTIONAL
{?artist
dbpedia-‐owl:deathPlace
?place_of_death
.}
FILTER
(!BOUND(?place_of_death))
EUCLID
-‐
Querying
Linked
Data
36
}
Create
the
dc:creator
descripCons
of
those
arCsts
who
are
not
dead.
Query:
NOT
EXISTS
{?artist
dbpedia-‐owl:deathPlace
?place_of_death
.}
37. Query
Form:
CONSTRUCT
(10)
Assigning
Variables
• The
value
of
an
expression
can
be
added
to
a
solu6on
mapping
by
binding
a
new
variable
(which
can
be
further
used
and
returned)
• The
BIND
form
allows
to
assign
a
value
to
a
variable
from
a
BGP
Calculate
the
duraCon
of
the
tracks
from
ms
to
s,
and
store
the
value
using
the
dbpedia-‐ont:runCme
property
.
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
mo:
<http://purl.org/ontology/mo/>
PREFIX
dbpedia-‐ont:
<http://dbpedia.org/ontology/>
CONSTRUCT
{
?track
dbpedia-‐ont:runtime
?secs
.}
WHERE
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
mo:track
?track
.
?track
mo:duration
?duration
.
BIND((?duration/1000)
AS
?secs)
.}
EUCLID
-‐
Querying
Linked
Data
37
Query:
38. Query
Form:
CONSTRUCT
(11)
Sub-‐queries
and
Aggregate
Values
• To
combine
the
CONSTRUCT
query
form
with
aggregate
values,
a
sub-‐query
should
be
created
inside
the
WHERE
clause
Materialize
the
duraCon
of
the
albums
recorded
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
PREFIX
mo:
<http://purl.org/ontology/mo/>
CONSTRUCT
{?album
music-‐ont:duration
?album_duration
.}
WHERE
{
SELECT
?album
(SUM(?track_duration)
AS
?album_duration)
{
dbpedia:The_Beatles
foaf:made
?album
.
?album
mo:track
?track
.
?track
mo:duration
?track_duration
.
}
GROUP
BY
?album
HAVING
(SUM(?track_duration)
>
3600000)}
EUCLID
-‐
Querying
Linked
Data
38
Query:
by
‘The
Beatles’.
40. Data
Management
SPARQL
1.1
provides
data
update
opera6ons:
• INSERT
EUCLID
-‐
Querying
Linked
Data
40
data:
adds
some
triples,
given
inline
in
the
request,
into
a
graph
• DELETE
data:
removes
some
triples,
given
inline
in
the
request,
if
the
respec6ve
graphs
contains
those
• DELETE/INSERT
data:
uses
in
parallel
INSERT
and
DELETE
CH
1
CH
1
41. Data
Management
(2)
Insert
the
following
albums
recorded
by
The
Beatles
into
the
graph
http://musicbrainz.org/20130209-‐004702
EUCLID
-‐
Querying
Linked
Data
41
INSERT
data
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
INSERT
DATA
{
GRAPH
{
<http://musicbrainz.org/20130302>
<http://musicbrainz.org/artist/b10bbbfc-‐cf9e-‐42e0-‐be17-‐e2c3e1d2600d>
foaf:made
<http://musicbrainz.org/release/3a685770-‐7326-‐34fc-‐9f18-‐e5f5626f3dc5>
,
<
http://musicbrainz.org/release/cb6f8798-‐d51e-‐4fa5-‐a4d1-‐2c0602bfe1b6
>
.
<http://musicbrainz.org/release/3a685770-‐7326-‐34fc-‐9f18-‐e5f5626f3dc5>
dc:title
"Please
Please
Me".
<
http://musicbrainz.org/release/cb6f8798-‐d51e-‐4fa5-‐a4d1-‐2c0602bfe1b6
>
dc:title
"Something
New".
}
}
CH
1
42. Data
Management
(3)
DELETE
data
Delete
all
the
information
about
the
album
Casualities
of
The
Beatles.
PREFIX
dc:
<http://purl.org/dc/elements/1.1/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
DELETE
{
?album
?predicate
?object
.
}
WHERE
{
<http://musicbrainz.org/artist/b10bbbfc-‐cf9e-‐42e0-‐be17-‐e2c3e1d2600d>
foaf:made
?album
.
?album
dc:title
"Casualities".
?album
?predicate
?object
.}
CH
1
EUCLID
-‐
Querying
Linked
Data
42
43. Data
Management
(4)
DELETE/INSERT
data
Delete
the
status
of
‘Peter
Best’
as
current
member
of´The
Beatles´,
and
insert
his
status
as
former
member
of
the
band.
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
db-‐ont:
<http://dbpedia.org/ontology/>
PREFIX
foaf:
<http://xmlns.com/foaf/0.1/>
DELETE
{
dbpedia:The_Beatles
db-‐ont:currentMember
?x
.
}
INSERT
{
GRAPH
<http://musicbrainz.org/20130209-‐004702>
{
dbpedia:The_Beatles
db-‐ont:formerBandMember
?x
.}
}
EUCLID
-‐
Querying
Linked
Data
43
WHERE
{
dbpedia:The_Beatles
db-‐ont:currentMember
?x
.
?x
foaf:name
"Peter
Best"
.}
44. Graph
Management
SPARQL
1.1
provides
graph
update
opera6ons:
• CREATE:
creates
an
empty
graph
in
the
Graph
Store
EUCLID
-‐
Querying
Linked
Data
44
• LOAD:
reads
the
content
of
a
document
into
a
graph
in
the
Graph
Store
• CLEAR:
removes
all
triples
in
one
or
more
graphs
• DROP:
removes
the
graph
from
the
Graph
Store
• Other
opera+ons:
COPY,
MOVE,
ADD
45. Graph
Management
(2)
CREATE
GRAPH
<http://musicbrainz.org/20130302>
LOAD
<http://xmlns.com/foaf/spec/20100809.rdf>
LOAD
<http://xmlns.com/foaf/spec/20100809.rdf>
INTO
<http://xmlns.com/foaf/0.1/>
EUCLID
-‐
Querying
Linked
Data
45
CREATE
• Creates
a
new
named
graph
• Can
be
used
with
the
DEFAULT
and
ALL
keywords
LOAD
• An
RDF
graph
can
be
loaded
from
a
URL
• LOAD
can
be
used
with
the
SILENT
keyword
Named
graph
46. Graph
Management
(3)
CLEAR
GRAPH
<http://musicbrainz.org/20130302>
EUCLID
-‐
Querying
Linked
Data
46
CLEAR
• Removes
all
triples
in
the
graph
(it
is
emp6ed
but
not
deleted!)
• The
graph(s)
can
be
specified
with
the
following
keywords:
DEFAULT,
NAMED,
ALL,
GRAPH
• Can
be
used
with
the
SILENT
keyword
DROP
• The
given
graph
is
removed
from
the
Graph
Store,
including
its
content
• Can
be
used
with
the
DEFAULT
and
ALL
keywords
DROP
GRAPH
<http://musicbrainz.org/20130302>
47. Graph
Management
(4)
SPARQL
1.1
provides
other
graph
management
opera6ons:
• COPY
COPY
GRAPH
<http://musicbrainz.org/20130302>
TO
GRAPH
<http://musicbrainz.org/20130303>
MOVE
GRAPH
<http://musicbrainz.org/temp>
TO
GRAPH
<http://musicbrainz.org/20130303>
EUCLID
-‐
Querying
Linked
Data
47
…
TO
…
• MOVE
…
TO
…
• ADD
…
TO
…
ADD
GRAPH
<http://musicbrainz.org/20130302>
TO
GRAPH
<http://musicbrainz.org/20130303>
49. SPARQL
1.1.
Protocol
EUCLID
-‐
Querying
Linked
Data
49
• Consists
of
two
opera+ons:
query
and
update
• An
opera6on
defines:
• The
HTTP
method
(GET
or
POST)
• The
HTTP
query
string
parameters
• The
message
content
included
in
the
HTTP
request
body
• The
message
content
included
in
the
HTTP
response
body
SPARQL
Client
SPARQL
Endpoint
Request
alt
[no errors]!
[else]!
Success
Response
Failure
Response
50. Query
Operation
XML,
JSON,
CSV/TSV
from
a
SELECT
EUCLID
-‐
Querying
Linked
Data
50
• Sends
a
SPARQL
query
to
a
service
and
receives
the
results
of
the
query
• The
response
is:
• May
be
invoked
using
HTTP
GET
or
HTTP
POST.
The
method
POST
with
URL
encoding
is
mostly
used
when
the
query
string
is
too
long
query
RDF/XML,
Turtle
from
a
CONSTRUCT
query
51. Query
Operation
(2)
EUCLID
-‐
Querying
Linked
Data
51
Example:
SPARQL
Query:
PREFIX
dbpedia:
<http://dbpedia.org/resource/>
PREFIX
dbpedia-‐ont:
<http://dbpedia.org/ontology/>
SELECT
?album
WHERE
{
?album
dbpedia-‐ont:artist
dbpedia:The_Beatles
.}
LIMIT
3
HTTP
GET
request:
Try
this
query!
(Click
on
the
hurl
icon)
52. Update
Operation
EUCLID
-‐
Querying
Linked
Data
52
• Sends
a
SPARQL
update
request
to
a
service
• Should
be
invoked
using
the
HTTP
PATCH/POST
method
• The
response
consists
of
a
HTTP
response
status
code,
which
indicates
success
or
failure
of
the
opera6on
54. Reasoning
for
Linked
Data
Integration
EUCLID
-‐
Querying
Linked
Data
54
• Example:
Integra6on
of
the
MusicBrainz
data
set
and
the
DBpedia
data
set
Integra+on
Data
set
Data
set
55. Reasoning
for
Linked
Data
Integration
mo:b10bbbfc-‐cf9e-‐42e0-‐be17-‐e2c3e1d2600d
dbpedia:The_Beatles
dbpedia-‐ont:origin
dbpedia:Liverpool;
dbpedia-‐ont:genre
dbpedia:Rock_music;
foaf:depiction
.
foaf:name
The
Beatles;
mo:member
mo:ba550d0e-‐adac-‐4864-‐b88b-‐407cab5e76af;
mo:member
mo:4d5447d7-‐c61c-‐4120-‐ba1b-‐d7f471d385b9;
mo:member
mo:42a8f507-‐8412-‐4611-‐854f-‐926571049fa0;
mo:member
mo:300c4c73-‐33ac-‐4255-‐9d57-‐4e32627f5e13.
Integra+on
EUCLID
-‐
Querying
Linked
Data
55
Data
set
Data
set
same
56. Reasoning
for
Linked
Data
Integration
same
mo:b10bbbfc-‐cf9e-‐42e0-‐be17-‐e2c3e1d2600d
dbpedia:The_Beatles
dbpedia-‐ont:origin
dbpedia:Liverpool;
dbpedia-‐ont:genre
dbpedia:Rock_music;
foaf:depiction
.
foaf:name
The
Beatles;
mo:member
mo:ba550d0e-‐adac-‐4864-‐b88b-‐407cab5e76af;
mo:member
mo:4d5447d7-‐c61c-‐4120-‐ba1b-‐d7f471d385b9;
mo:member
mo:42a8f507-‐8412-‐4611-‐854f-‐926571049fa0;
mo:member
mo:300c4c73-‐33ac-‐4255-‐9d57-‐4e32627f5e13.
Result
set:
EUCLID
-‐
Querying
Linked
Data
56
Query:
SELECT
?m
?g
WHERE
{
dbpedia:The_Beatles
dbpedia-‐ont:genre
?g;
mo:member
?m.}
?m
?g
mo:ba550d0e-‐adac-‐4864-‐
b88b-‐407cab5e76af
dbpedia:Rock_music
mo:4d5447d7-‐c61c-‐4120-‐ba1b-‐
d7f471d385b9
dbpedia:Rock_music
mo42a8f507-‐8412-‐4611-‐854f-‐92
6571049fa0;
dbpedia:Rock_music
mo300c4c73-‐33ac-‐4255-‐9d57-‐4e
32627f5e13
dbpedia:Rock_music
57. SPARQL
1.1:
Entailment
Regimes
EUCLID
-‐
Querying
Linked
Data
57
• SPARQL
1.0
was
defined
only
for
simple
entailment
(paern
matching
)
• SPARQL
1.1
is
extended
with
entailment
regimes
other
than
simple
entailment:
– RDF
entailment
– RDFS
entailment
– D-‐Entailment
– OWL
RL
entailment
– OWL
Full
entailment
– OWL
2
DL,
EL,
and
QL
entailment
– RIF
entailment
Source:
hp://www.w3.org/TR/rdf-‐mt/#RDFSRules
58. RDFS
Resource
Descrip+on
Framework
Schema
Seman6c
Web
Stack
Berners-‐Lee
(2006)
EUCLID
-‐
Querying
Linked
Data
58
Taxonomies
and
inferences
60. rdfs2
–
rdfs:domain
dbpedia:
The_Beatles
EUCLID
-‐
Querying
Linked
Data
60
dbpedia:
Paul_McCartney
SELECT
?x
WHERE
{
?x
a
mo:MusicGroup.}
mo:member
rdfs:domain
mo:MusicGroup
.
?x
?x
dbpedia:The_Beatles
…
mo:member
Schema:
Query:
Result
set:
Result
set
with
inference:
dbpedia:
John_Lennon
dbpedia:
George_Harrison
dbpedia:
Ringo_Starr
mo:member
mo:member
mo:member
61. rdfs3
–
rdfs:range
dbpedia:
The_Beatles
dbpedia-‐ont:
bandMember
EUCLID
-‐
Querying
Linked
Data
61
dbpedia:
Paul_McCartney
SELECT
?x
WHERE
{
?x
a
foaf:Agent.}
mo:member
rdfs:range
foaf:Agent
.
?x
?x
dbpedia:Paul_McCartney
dbpedia:John_Lennon
dbpedia:Ringo_Starr
dbpedia:George_Harrison
…
dbpedia-‐ont:
bandMember
Schema:
Query:
Result
set:
Result
set
with
inference:
dbpedia:
John_Lennon
dbpedia:
George_Harrison
dbpedia:
Ringo_Starr
dbpedia-‐ont:
bandMember
dbpedia-‐ont:
bandMember
62. rdfs7
–
rdfs:subPropertyOf
dbpedia:
Yesterday
EUCLID
-‐
Querying
Linked
Data
62
dbpedia:
Paul_McCartney
SELECT
?x
WHERE
{
dbpedia:Yesterday
mo:performer
?x.}
mo:singer
rdfs:subPropertyOf
mo:performer
.
?x
dbpedia:John_Lennon
dbpedia:Ringo_Starr
dbpedia:George_Harrison
?x
dbpedia:John_Lennon
dbpedia:Ringo_Starr
dbpedia:George_Harrison
dbpedia:Paul_McCartney
mo:singer
Schema:
Query:
Result
set:
Result
set
with
inference:
dbpedia:
John_Lennon
dbpedia:
George_Harrison
dbpedia:
Ringo_Starr
mo:performer
mo:performer
mo:performer
mo:performer
63. rdfs9
–
rdfs:subClassOf
mo:
MusicAr6st
EUCLID
-‐
Querying
Linked
Data
63
dbpedia:
The_Beatles
SELECT
?x
WHERE
{
?x
a
mo:MusicArtist.}
rdf:type
mo:MusicGroup
rdfs:subClassOf
mo:MusicArtist
.
?x
?x
dbpedia:The_Beatles
…
Schema:
Query:
Result
set:
Result
set
with
inference:
rdf:type
mo:
MusicGroup
64. Inference
from
Schema
mo:MusicGroup
rdfs:subClassOf
mo:MusicArtist
.
mo:MusicGroup
a
rdfs:Class
.
mo:MusicArtist
a
rdfs:Class
.
EUCLID
-‐
Querying
Linked
Data
64
• Knowledge
encoded
in
the
schema
leads
to
infer
new
facts
Schema:
Inferred
facts:
• This
is
also
captured
in
the
set
of
axioma+c
triples,
which
provide
basic
meaning
for
all
the
vocabulary
terms
rdfs:subClassOf
rdfs:domain
rdfs:Class
.
rdfs:subClassOf
rdfs:range
rdfs:Class
.
65. RDFS:
Lack
of
Consistency
Check
rdfs2
EUCLID
-‐
Querying
Linked
Data
65
• It
is
possible
to
infer
facts
that
seem
incorrect
facts,
but
RDFS
cannot
prevent
this:
Schema:
mo:member
rdfs:domain
mo:MusicGroup
;
rdfs:range
foaf:Agent
.
Exis6ng
:PaulMcCartney
a
:SoloMusicArtist
;
facts:
:member
:TheBeatles
.
Inferred
:PaulMcCartney
a
:MusicGroup
.
facts:
No
contradic+on!:
The
mis-‐modeling
is
not
diagnosed
66. • We
might
wish
further
inferences,
but
these
are
beyond
the
entailment
rules
implemented
by
RDFS
RDFS:
Inference
Limitations
Cannot
model
with
RDFS
that
if
‘x
makes
y’
implies
that
‘the
creator
of
y
is
x’
EUCLID
-‐
Querying
Linked
Data
66
foaf:knows
rdfs:domain
foaf:Person
;
rdfs:range
foaf:Person
.
foaf:made
rdfs:domain
foaf:Agent
.
:PaulMcCartney
foaf:made
:Yesterday
;
foaf:knows
:RingoStarr
.
:PaulMcCartney
a
foaf:Agent
;
a
foaf:Person
.
:RingoStarr
a
foaf:Person
.
Schema:
Existing
fact:
Inferred
facts:
:Yesterday
dc:creator
:PaulMcCartney.
:RingoStarr
foaf:knows
:PaulMcCartney
.
These
inferences
require
OWL!
NOT
inferred:
Cannot
model
with
RDFS
that
‘x
knows
y’
implies
‘y
knows
x’
67. OWL
Web
Ontology
Language
Seman6c
Web
Stack
Berners-‐Lee
(2006)
EUCLID
-‐
Querying
Linked
Data
67
Ontologies
and
inferences
68. Introduction
to
OWL
More
restric6ve
than
OWL
DL
EUCLID
-‐
Querying
Linked
Data
68
• Provides
more
ontological
constructs
and
avoids
some
of
the
poten6al
confusion
in
RDFS
• OWL
2
is
divided
into
sub-‐languages
denominated
profiles:
– OWL
2
EL:
Limited
to
basic
classifica6on,
but
with
polynomial-‐6me
reasoning
– OWL
2
QL:
Designed
to
be
translatable
to
rela6onal
database
querying
– OWL
2
RL:
Designed
to
be
efficiently
implementable
in
rule-‐based
systems
• Most
triple
stores
concentrate
on
the
use
of
RDFS
with
a
subset
of
OWL
features,
called
OWL-‐Horst
or
RDFS++
69. OWL
Properties
OWL
dis6nguishes
between
two
types
of
proper6es:
• OWL
ObjectProper+es:
resources
as
values
EUCLID
-‐
Querying
Linked
Data
69
• OWL
DatatypeProper+es:
literals
as
values
:plays
rdf:type
owl:ObjectProperty;
rdfs:domain
:Musician;
rdfs:range
:Instrument
.
:hasMembers
rdf:type
owl:DatatypeProperty;
rdfs:domain
:MusicGroup
rdfs:range
xsd:int
.
70. Property
Axioms
SELECT
?x
{dbpedia:The_Beatles
dbpedia-‐ont:bandMember
?x.}
Result
set
with
inference:
EUCLID
-‐
Querying
Linked
Data
70
• Property
axioms
include
those
from
RDF
Schema
• OWL
allows
for
property
equivalence.
Example:
EquivalentObjectProperties(dbpedia-‐ont:bandMember
mo:member)
≡
dbpedia-‐ont:bandMember
owl:equivalentProperty
mo:member.
dbpedia:
The_Beatles
dbpedia:
John_Lennon
mo:member
dbpedia:
Paul_McCartney
dbpedia:
George_Harrison
dbpedia:
Ringo_Starr
mo:member
mo:member
mo:member
Query:
?x
Result
set:
?x
dbpedia:Paul_McCartney
dbpedia:John_Lennon
dbpedia:Ringo_Starr
dbpedia:George_Harrison
71. Property
Axioms
EUCLID
-‐
Querying
Linked
Data
71
• Property
axioms
include
those
from
RDF
Schema
• OWL
allows
for
property
equivalence.
Example:
EquivalentObjectProperties(dbpedia-‐ont:bandMember
mo:member)
dbpedia-‐ont:bandMember
owl:equivalentProperty
mo:member.
• OWL
allows
for
property
disjointness.
Example:
DisjointObjectProperty(dbpedia-‐ont:length
mo:duration)
dbpedia-‐ont:length
owl:propertyDisjointWith
mo:duration.
• There
is
no
standard
for
implemen6ng
inconsistency
reports
under
SPARQL
≡
≡
72. Property
Axioms
(2)
OWL
allows
the
defini6on
of
property
characteris6cs
to
infer
new
facts
rela6ng
to
instances
and
their
proper6es
• Symmetry
• Transi6vity
• Inverse
• Func6onal
• Inverse
Func6onal
EUCLID
-‐
Querying
Linked
Data
72
73. Property
Axioms:
Symmetry
Query:
SELECT
?x
WHERE
{
dbpedia:The_Beatles
:associatedMusicalArtist
?x.}
EUCLID
-‐
Querying
Linked
Data
73
dbpedia:
Plas6c_Ono_
Band
dbpedia:
The_Beatles
dbpedia:
Billy_Preston
:associatedMusicalArtist
a
owl:SymmetricProperty
.
?genre
dbpedia:Plastic_Ono_Band
?genre
dbpedia:Plastic_Ono_Band
dbpedia:Billy_Preston
:associatedMusicalArtist
Schema:
Result
set:
Result
set
with
inference:
:associatedMusicalArtist
74. Property
Axioms:
Transitivity
:subgenre
a
owl:TransitiveProperty
.
EUCLID
-‐
Querying
Linked
Data
74
:Rock
:Heavy_
metal
:Black_
metal
:Punk_
rock
SELECT
?genre
WHERE
{
:Rock
:subgenre
?genre
.}
?genre
:Heavy_metal
:Punk_rock
?genre
:Heavy_metal
:Punk_rock
:Black_metal
:subgenre
:subgenre
:subgenre
:subgenre
Schema:
Query:
Result
set:
Result
set
with
inference:
75. Property
Axioms:
Inverse
Schema:
mo:member_of
owl:inverseOf
mo:member.
Query:
SELECT
?x
WHERE
{
?x
mo:member_of
dbpedia:The_Beatles
.}
EUCLID
-‐
Querying
Linked
Data
75
?x
dbpedia:
John_Lennon
mo:member_of
dbpedia:John_Lennon
dbpedia:George_Harrison
?x
dbpedia:John_Lennon
dbpedia:George_Harrison
dbpedia:Paul_McCartney
dbpedia:Ringo_Starr
Result
set:
Result
set
with
inference:
dbpedia:
The_Beatles
dbpedia:
Paul_McCartney
dbpedia:
George_Harrison
dbpedia:
Ringo_Starr
mo:member
mo:member_of
mo:member
mo:member_of
mo:member_of
76. Property
Axioms:
Functional
It
refers
to
a
property
that
can
have
only
one
(unique)
value
for
each
instance
Example:
Every
ar6st
primarily
plays
only
one
musical
instrument
r1
r2
mo:primary_
instrument
same
mo:primary_
instrument
mo:primary_instrument
rdf:type
owl:FunctionalProperty
.
dbpedia:Jimi_Hendrix
mo:primary_instrument
dbpedia:Electric_Guitar.
dbpedia:Jimi_Hendrix
mo:primary_instrument
dbpedia:E-‐Guitar.
Conclusion
dbpedia:Electric_Guitar
owl:sameAs
dbpedia:E-‐Guitar
.
EUCLID
-‐
Querying
Linked
Data
76
77. Property
Axioms:
Inverse
Functional
It
is
useful
for
specifying
unique
proper6es
iden6fying
Example:
Every
recording
has
a
unique
ISRC
(Interna6onal
Standard
Recording
Code)
mo:isrc
rdf:type
owl:InverseFunctionalProperty
.
mo:21047249-‐7b3f-‐4651-‐acca-‐246669c081fd
mo:isrc
"GBAYE6300412"
.
dbpedia:She_Loves_You
mo:isrc
"GBAYE6300412"
.
Conclusion
mo:21047249-‐7b3f-‐4651-‐acca-‐246669c081fd
owl:sameAs
:dbpedia:She_Loves_You
.
EUCLID
-‐
Querying
Linked
Data
77
an
individual
r2
mo:isrc
mo:isrc
same
r1
78. Individual
Axioms
OWL
Individuals
represent
instances
of
classes.
They
are
related
to
their
class
by
the
rdf:type
property
EUCLID
-‐
Querying
Linked
Data
78
• We
can
state
that
two
individuals
are
the
same
SameIndividual(<artist/ba550d0e-‐adac-‐4864-‐b88b-‐407cab5e76af#_>
dbpedia:PaulMcCartney)s
≡
<artist/ba550d0e-‐adac-‐4864-‐b88b-‐407cab5e76af#_>
owl:sameAs
dbpedia:PaulMcCartney
.
• We
can
state
that
two
individuals
are
different
DifferentIndividuals(:TheBeatles_band
:TheBeatles_TVseries)
≡
:TheBeatles_band
owl:differentFrom
:TheBeatles_Tvseries
.
79. Class
Axioms
Axioms
declare
general
statements
about
concepts
which
are
used
in
logical
inference
(reasoning).
Class
axioms:
• Sub-‐class
rela6onship
(from
RDF
Schema)
EUCLID
-‐
Querying
Linked
Data
79
• Equivalent
rela6onship:
classes
have
the
same
individuals
EquivalentClass(:Musician
:MusicArtist)
≡
:Musician
owl:equivalentClass
:MusicArtist
.
• Disjointness:
classes
have
no
shared
individuals
DisjointClasses(:SoloMusicArtist
:MusicGroup)
≡
:SoloMusicArtist
owl:disjointWith
:MusicGroup
.
80. Class
Construction
Ar6st
EUCLID
-‐
Querying
Linked
Data
80
• OWL
classes
are
defined
by
the
OWL
term
owl:Class
• OWL
classes
can
be
subclassed
as
in
RDFS:
• OWL
classes
may
be
combined
with
class
constructs
to
build
new
classes
Music
Ar6st
:MusicArtist
rdfs:subClassOf
:Artist
.
81. Class
Construction
(2)
These
class
constructs
are
available
in
OWL,
not
in
RDFS
The
class
of
female
music
ar6sts
ObjectIntersectionOf(:Female
:MusicArtist)s
[a
owl:Class;
owl:intersectionOf(:Female
:MusicArtist)]
The
class
of
music
ar6sts
ObjectUnionOf(:SoloMusicArtist
:MusicGroup)
[a
owl:Class;
owl:unionOf(:SoloMusicArtist
:MusicGroup)]
Everything
that’s
not
instrumental
music
ObjectComplementOf(:InstrumentalMusic)
[a
owl:Class;
owl:complementOf(:InstrumentalMusic)]
Female
Music
Ar6st
Solo
Group
Instrumental
EUCLID
-‐
Querying
Linked
Data
81
≡
≡
≡
NOTE:
Anonymous
classes!
82. Naming
Class
Constructions
EUCLID
-‐
Querying
Linked
Data
82
• Direct
naming
can
be
achieved
via
owl:equivalentClass
• This
construc6on
provides
necessary
and
sufficient
condi6ons
for
class
membership
• Class
naming
can
be
also
achieved
using
rdfs:subClassOf,
it
provides
a
necessary
but
insufficient
condi6on
for
class
membership
Music
Ar6st
Solo
Group
EquivalentClass(:MusicArtist
ObjectUnionOf(:SoloMusicArtist
:MusicGroup))
:MusicArtist
owl:equivalentClass
[owl:unionOf
(:SoloMusicArtist
:MusicGroup)]
≡
84. Summary
(2)
In
this
chapter
we
studied:
EUCLID
-‐
Querying
Linked
Data
84
• Reasoning
over
Linked
Data:
• SPARQL
1.1
entailment
regimes
• RDFS:
entailment
regimes,
lacks
of
consistency
check,
inference
limita6ons
• OWL:
proper6es,
property
axioms
(symmetry,
transi6vity,
inverse,
func6onal,
inverse
func6onal),
individual
axioms,
class
axioms,
class
construc6ons,
naming
classes
…
Reasoning
over
Linked
Data
85. For
exercises,
quiz
and
further
material
visit
our
website:
http://www.euclid-‐project.eu
EUCLID
-‐
Providing
Linked
Data
85
eBook
@euclid_project
euclidproject
euclidproject
Other
channels:
Course
86. Acknowledgements
• Alexander
Mikroyannidis
• Alice
Carpen6er
• Andreas
Harth
• Andreas
Wagner
• Andriy
Nikolov
• Barry
Norton
• Daniel
M.
Herzig
• Elena
Simperl
• Günter
Ladwig
• Inga
Shamkhalov
• Jacek
Kopecky
• John
Domingue
• Juan
Sequeda
• Kalina
Bontcheva
• Maria
Maleshkova
• Maria-‐Esther
Vidal
• Maribel
Acosta
• Michael
Meier
• Ning
Li
• Paul
Mulholland
• Peter
Haase
• Richard
Power
• Steffen
Stadtmüller
86
People
who
have
contributed
to
crea6ng
Euclid
training
content:
