TRACKER3-SPARQL(1) Tracker manual TRACKER3-SPARQL(1)
NAME
tracker3-sparql - Use SparQL to query the Tracker databases.
SYNOPSIS
tracker3 sparql -q <sparql> [-u] | -f <file>
tracker3 sparql -t [class] [-s <needle>] [-p]
tracker3 sparql [-c] [-p] [-x] [-n [class]] [-i [property]] [-s <needle>]
tracker3 sparql [--get-longhand <class>] [--get-shorthand <class>]
DESCRIPTION
This command allows probing of the current database schema (also known
as ontology) and running low level queries or updates on the data set.
In terms of the database ontology, it’s easy to find out what
properties are indexed for speed, or notified on changes, what classes
are available and the properties belonging to those classes. There are
also visual tools to display an ascii tree layout of the classes and
their relationships to each other.
When the caller runs a query, the query is in RDF and SPARQL. This can
be done two ways. Either by providing a file with the query or by
providing a string with the sparql query.
The file argument can be either a local path or a URI. It also does not
have to be an absolute path.
OPTIONS
-f, --file=<file>
Use a file with SPARQL content to query or update.
-q, --query=<sparql>
Use a sparql string to query the database with.
-u, --update
This has to be used with --query. This tells "tracker3 sparql" to
use the SPARQL update extensions so it knows it isn’t a regular
data lookup request. So if your query is intended to change data in
the database, this option is needed.
-c, --list-classes
Returns a list of classes which describe the ontology used for
storing data. These classes are also used in queries. For example,
http://www.w3.org/2000/01/rdf-schema#Resource is one of many
classes which should be returned here.
-x, --list-class-prefixes
Returns a list of classes and their related prefixes. Prefixes are
used to make querying a lot simpler and are much like an alias. For
example, http://www.w3.org/2000/01/rdf-schema#Resource has the
prefix rdfs so queries can be cut down to:
"SELECT ?u WHERE \{ ?u a rdfs:Resource }"
-p, --list-properties=[class]
Returns a list of properties which pertain to a class. You can use
both formats here for the class, either the full name
http://tracker.api.gnome.org/ontology/v3/nfo#Video or the shortened
prefix name nfo:Video.
This gives the following result:
$ tracker3 sparql -p nfo:Video
Properties: 2
http://tracker.api.gnome.org/ontology/v3/nfo#frameRate
http://tracker.api.gnome.org/ontology/v3/nfo#frameCount
These properties nfo:frameRate and nfo:frameCount can then be used in
queries.
See also --tree and --query.
-n, --list-notifies=[class]
Returns a list of classes which are notified over D-Bus about any
changes that occur in the database. The class does not have to be
supplied here. This is optional and filters the results according
to any argument supplied. With no class, all classes are listed.
-i, --list-indexes=[property]
Returns a list of properties which are indexed in the database.
Indexes improves query speed but also add an indexing penalty. The
property does not have to be supplied here. This is optional and
filters the results according to any argument supplied. With no
property, all properties are listed.
• -g, --list-graphs:: List all the named graphs in the database.
These are used by the filesystem miner to separate metadata so
that apps can only see the information relevant to them.
-t, --tree=[class]
Prints a tree showing all parent classes of class in the ontology.
The class can be provided in shorthand or longhand (see
--get-shorthand and --get-longhand for details). For example:
$ tracker3 sparql -t nmo:MMSMessage
ROOT
+-- rdfs:Resource (C)
| +-- nie:InformationElement (C)
| | +-- nfo:Document (C)
| | | +-- nfo:TextDocument (C)
| | | | `-- nmo:Message (C)
| | | | | +-- nmo:PhoneMessage (C)
| | | | | | `-- nmo:MMSMessage (C)
If no class is given, the entire tree is shown.
The --search command line option can be used to highlight parts of the
tree you’re looking for. The search is case insensitive.
The --properties command line option can be used to show properties for
each class displayed, for example:
$ tracker3 sparql -t nfo:FileDataObject -p
ROOT
+-- rdfs:Resource (C)
| --> http://purl.org/dc/elements/1.1/contributor (P)
| --> http://purl.org/dc/elements/1.1/coverage (P)
| --> http://purl.org/dc/elements/1.1/creator (P)
| --> http://purl.org/dc/elements/1.1/date (P)
| --> http://purl.org/dc/elements/1.1/description (P)
| --> http://purl.org/dc/elements/1.1/format (P)
| --> http://purl.org/dc/elements/1.1/identifier (P)
| --> http://purl.org/dc/elements/1.1/language (P)
| --> http://purl.org/dc/elements/1.1/publisher (P)
| --> http://purl.org/dc/elements/1.1/relation (P)
| --> http://purl.org/dc/elements/1.1/rights (P)
| --> http://purl.org/dc/elements/1.1/source (P)
| --> http://purl.org/dc/elements/1.1/subject (P)
| --> http://purl.org/dc/elements/1.1/title (P)
| --> http://purl.org/dc/elements/1.1/type (P)
| --> nao:deprecated (P)
| --> nao:hasTag (P)
| --> nao:identifier (P)
| --> nao:isRelated (P)
| --> nao:lastModified (P)
| --> nao:numericRating (P)
| --> rdf:type (P)
| --> rdfs:comment (P)
| --> rdfs:label (P)
| --> nrl:added (P)
| --> nrl:damaged (P)
| --> nrl:modified (P)
| +-- nie:DataObject (C)
| | --> nfo:belongsToContainer (P)
| | --> nie:byteSize (P)
| | --> nie:created (P)
| | --> nie:dataSource (P)
| | --> nie:interpretedAs (P)
| | --> nie:isPartOf (P)
| | --> nie:lastRefreshed (P)
| | --> nie:url (P)
| | --> tracker:available (P)
| | +-- nfo:FileDataObject (C)
| | | --> nfo:fileCreated (P)
| | | --> nfo:fileLastAccessed (P)
| | | --> nfo:fileLastModified (P)
| | | --> nfo:fileName (P)
| | | --> nfo:fileOwner (P)
| | | --> nfo:fileSize (P)
| | | --> nfo:hasHash (P)
| | | --> nfo:permissions (P)
-s, --search=<needle>
Returns a list of classes and properties which partially match
needle in the ontology. This is a case insensitive match, for
example:
$ tracker3 sparql -s text
Classes: 4
http://tracker.api.gnome.org/ontology/v3/nfo#TextDocument
http://tracker.api.gnome.org/ontology/v3/nfo#PlainTextDocument
http://tracker.api.gnome.org/ontology/v3/nfo#PaginatedTextDocument
http://tracker.api.gnome.org/ontology/v3/nmm#SynchronizedText
Properties: 4
http://tracker.api.gnome.org/ontology/v3/tracker#fulltextIndexed
http://tracker.api.gnome.org/ontology/v3/nie#plainTextContent
http://tracker.api.gnome.org/ontology/v3/nmo#plainTextMessageContent
http://tracker.api.gnome.org/ontology/v3/scal#textLocation
See also --tree.
--get-shorthand=<class>
Returns the shorthand for a class given by a URL. For example:
$ tracker3 sparql --get-shorthand http://tracker.api.gnome.org/ontology/v3/nmo#plainTextMessageContent
nmo:plainTextMessageContent
--get-longhand=<class>
Returns the longhand for a class given in the form of
CLASS:PROPERTY. For example:
$ tracker3 sparql --get-longhand nmm:MusicPiece
http://tracker.api.gnome.org/ontology/v3/nmm#MusicPiece
EXAMPLES
List all classes
$ tracker3 sparql -q "SELECT ?cl WHERE { ?cl a rdfs:Class }"
List all properties for the Resources class (see --list-properties)
$ tracker3 sparql -q "SELECT ?prop WHERE {
?prop a rdf:Property ;
rdfs:domain <http://www.w3.org/2000/01/rdf-schema#Resource>
}"
List all class namespace prefixes
$ tracker3 sparql -q "SELECT ?prefix ?ns WHERE {
?ns a nrl:Namespace ;
nrl:prefix ?prefix
}"
List all music files
$ tracker3 sparql -q "SELECT ?song WHERE { ?song a nmm:MusicPiece }"
List all music albums, showing title, track count, and length in
seconds.
$ tracker3 sparql -q "SELECT ?title COUNT(?song)
AS songs
SUM(?length) AS totallength
WHERE {
?album a nmm:MusicAlbum ;
nie:title ?title .
?song nmm:musicAlbum ?album ;
nfo:duration ?length
} GROUP BY ?album"
List all music from a particular artist
$ tracker3 sparql -q "SELECT ?song ?title WHERE {
?song nmm:performer [ nmm:artistName 'Artist Name' ] ;
nie:title ?title
}"
Set the played count for a song
$ tracker3 sparql -u -q "DELETE {
<file:///home/user/Music/song.mp3> nie:usageCounter ?count
} WHERE {
<file:///home/user/Music/song.mp3> nie:usageCounter ?count
} INSERT {
<file:///home/user/Music/song.mp3> nie:usageCounter 42
}"
List all image files
$ tracker3 sparql -q "SELECT ?image WHERE { ?image a nfo:Image }"
List all image files with a specific tag
$ tracker3 sparql -q "SELECT ?image WHERE {
?image a nfo:Image ;
nao:hasTag [ nao:prefLabel 'tag' ]
}"
List all image files created on a specific month and order by date
$ tracker3 sparql -q "SELECT ?image ?date WHERE {
?image a nfo:Image ;
nie:contentCreated ?date .
FILTER (?date >= '2008-07-01T00:00:00' &&
?date < '2008-08-01T00:00:00')
} ORDER BY ?date"
SEE ALSO
tracker3-sql(1), tracker3-info(1).
http://nepomuk.semanticdesktop.org/
http://www.w3.org/TR/rdf-sparql-query/
3.4.2 12/06/2022 TRACKER3-SPARQL(1)
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