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NAME

wdq - command line access to Wikidata Query Service

SYNOPSIS

Access Wikidata Query Service via command line to perform SPARQL queries (query mode), lookup entities (lookup), or search items and properties (search or psearch):

wdq -g en solar system        # search 'solar system' in English
wdq psearch -g es parte       # search property 'parte' in Spanish
wdq P361 Q544                 # lookup properties and items
wdq '?c wdt:P361 wd:Q544'     # query parts of the solar system

See the manual for details or get help via wdq help:

wdq help options              # list and explain command line options
wdq help modes                # list and explain request modes
wdq help output               # explain output control
wdq help formats              # list and explain output formats
wdq help ontology             # show Wikidata ontology in a nutshell
wdq help prefixes             # list RDF prefixes allowed in queries
wdq help version              # show version of wdq

DESCRIPTION

The command line script wdq, included in CPAN module App::wdq, provides a tool to access Wikidata Query Service. It supports formulation and execution of SPARQL SELECT queries to extract selected information from Wikidata or other Wikibase instances.

INSTALLATION

Perl should already installed at most operating systems. Otherwise get Perl!

FROM CPAN

Install sources from CPAN including all dependencies:

cpanm App::wdq

First install cpanm if missing. If installation of App::wdq fails try cpanm option --notest or install dependencies as packages as described below.

PREBUILD PACKAGES

Install dependencies as prebuild packages for your operating system:

# Debian based systems e.g. Ubuntu (>= 14.04)
sudo apt-get install libhttp-tiny-perl librdf-query-perl

# Windows/ActiveState
ppm install HTTP-Tiny
ppm install RDF-Query

Then install wdq from CPAN as described above or copy the script to some place in your $PATH:

wget https://github.com/nichtich/wdq/raw/master/script/wdq
chmod +x wdq

The latter method will not install this documentation.

MODES

Request mode query (default), lookup, serch, or psearch can explicitly be set via first argument or it's guessed from arguments.

query

Read SPARQL query from STDIN, option --query|-q, or argument. Namespace definitions and SELECT clause are added if missing.

wdq '?c wdt:P361 wd:Q544'
wdq '{ ?c wdt:P361 wd:Q544 }'                 # equivalent
wdq 'SELECT * WHERE { ?c wdt:P361 wd:Q544 }'  # equivalent
wdq < queryfile

lookup

Read Wikidata entity ids, URLs, or Wikimedia project URLs from STDIN or arguments. Result fields are label, description, and id:

wdq Q1
wdq lookup Q1                                 # equivalent
echo Q1 | wdq lookup                          # equivalent
wdq http://de.wikipedia.org/wiki/Universum    # same result

search / psearch

Search for items or properties. Result fields are label, id, description, and possibly matched alias. Search and result language is read from environment or option --language/-g:

wdq search -g sv Pippi Långstrump

Default output format in search mode is text.

OPTIONS

--query|-q QUERY

Query or query file (- for STDIN as default)

--format|-f FORMAT|TEMPLATE

Output format or string template. Call wdq help formats for details.

--export EXPORTER

Use a Catmandu exporter as output format.

--no-header|-H

Exclude header in CSV output or other exporter.

--enumerate|-e

Enumerate results by adding a counter variable n

--limit INTEGER

Add or override a LIMIT clause to limitate the number of results. Single-digit options such as -1 can also be used to also set a limit.

--ids|-i

Abbreviate Wikidata identifier URIs as strings.

--language|-g

Language to query labels and descriptions in. Set to the locale by default. This option is currentl only used on lookup mode.

--count|-c VARS

Prepend SPARQL QUERY to count distinct values

--label|-l VARS
--description|-d VARS
--text|-t VARS

Add label, description, or both. Adds label/description for variable id or xLabel/xDescription for any x.

--ignore

Ignore empty results instead of issuing warning and exit code.

--color|-C

By default output is colored if writing to a terminal. Disable this with --no-color, --monochrome, or -M. Force color with --color or -C.

--api URL

SPARQL endpoint. Default value: https://query.wikidata.org/bigdata/namespace/wdq/sparql

--no-mediawiki|-m

Don't query MediaWiki API to map URLs to Wikidata items.

--no-execute|-n

Don't execute SPARQL queries but show them in expanded form. Useful to validate and pretty-print queries. MediaWiki API requests may be

-N

Don't execute any queries. Same as --no-mediawiki --no-execute.

--help|-h|-?

Show usage help

--ontology

Show information about the Wikidata Ontology

--no-default-prefixes

Don't add default namespace prefixes to the SPARQL query

--man

Show detailled manual

--version|-V

Show version if this script

OUTPUT

Output can be controlled with options --format/-f, --export, --header/--no-header/-H, and --color/--no-color/-C.

Formats

Option --format/-f sets an output format or string template:

simple (default in query and lookup mode)

Flat JSON without language tags

text (default in search mode)

Print label, alias, id and description or count when counting. Also sets option --ids.

ldjson

Line delimited Flat JSON

csv

SPARQL Query Results CSV Format. Suppress header with option --no-header/-H. Use Catmandu CSV exporter for more options

tsv

SPARQL Query Results TSV Format

xml

SPARQL Query Results XML Format

json

SPARQL Query Results JSON Format

...

String template. Call wdq help pretty for details

Pretty

Option --format can be set to a string template with bracket expressions with optional template parameters (for instance {id|pre= (|post=)}).

style

Highlight n name, v value, i identifier, t title, or e error

length

Abbreviate long values

align

Use left or right to align short values to a given length

pre/post

Add string before/after value

Export

Option --export sets a Catmandu exporter to create output with. Given the corresponding exporter modules installed, one can write results as YAML, Excel (XLS), and Markdown table (Table) among other formats:

wdq --export YAML                               # short form
wdq --format ldjson | catmandu convert to YAML  # equivalent

Use Catmandu config file (catmandu.yml) to further configure export. See also tools such as jq and miller for processing results.

EXAMPLES

# search "solar system" in English (=> Q544)
wdq -g en solar system

# search part-of property (=> P361)
wdq psearch -g en part

# get all parts of the solar system
wdq '?c wdt:P361 wd:Q544'

# look up label and description
wdq Q42 P9

# look up German Wikipedia article and get label description in French
wdq -g fr http://de.wikipedia.org/wiki/Argon

# get all references used at an item
wdq 'wd:Q1 ?prop [ prov:wasDerivedFrom ?ref ]'

# get doctoral advisor graph (academic genealogy) as CSV
wdq '?student wdt:P184 ?advisor' --ids --format csv

# print expanded SPARQL query
wdq -n '?c wdt:P361 wd:Q544'

# execute query and return first 10 tab-separated values
wdq -f tsv --limit 10 < query

# print result as Markdown Table (requires Catmandu::Exporter::Table)
wdq --export Table < query

# count instances (P31) of books (Q571)
wdq --count x '?x wdt:P31 wd:Q571'

# list types (P279) of Exoplanets (Q44559) with label and description
wdq '?id wdt:P279 wd:Q44559:' --text id --format text

WIKIDATA ONTOLOGY

Entity (item/property)
 wd:Q* <-- owl:sameAs --> wd:Q*
       --> rdfs:label, skos:altLabel, schema:description "*"@*
       --> schema:dateModified, schema:version
       --> wdt:P* "*", URI, _:blank
       --> p:P* Statement

Item
 wd:Q* <-- schema:about <http://*.wikipedia.org/wiki/*>
                          --> schema:inLanguage, wikibase:badge

Property
 wd:P* --> wikibase:propertyType PropertyType
       --> wkibase:directClaim        wdt:P*
       --> wikibase:claim             p:P*
       --> wikibase:statementProperty ps:P*
       --> wikibase:statementValue    psv:P*
       --> wikibase:qualifier         pq:P*
       --> wikibase:qualifierValue    pqv:P*
       --> wikibase:reference         pr:P*
       --> wikibase:referenceValue    prv:P*
       --> wikibase:novalue           wdno:P*

PropertyType
 wikibase: String, Url, WikibaseItem, WikibaseProperty, CommonsMedia, Math,
           Monolingualtext, GlobeCoordinate, Quantity, Time, ExternalId


Statement
 wds:* --> wikibase:rank Rank
       --> a wdno:P*
       --> ps:P* "*", URI, _:blank
       --> psv:P* Value
       --> pq:P* "*", URI, _:blank
       --> pqv:P* Value
       --> prov:wasDerivedFrom Reference

Reference
 wdref:* --> pr:P* "*", URI
         --> prv:P* Value

Rank
 wikibase: NormalRank, PreferredRank, DeprecatedRank, BestRank

Value (GlobecoordinateValue/QuantityValue/TimeValue)
 wdv:* --> wikibase: geoLatitude, geoLongitude, geoPrecision, geoGlobe URI
       --> wikibase: timeValue, timePrecision, timeTimezone, timeCalendarModel
       --> wikibase: quantityAmount, quantityUpperBound, quantityLowerBound,
                     quantityUnit URI

COPYRIGHT AND LICENSE

Copyright by Jakob Voss voss@gbv.de

Based on a PHP script by Marius Hoch hoo@online.de at https://github.com/mariushoch/asparagus.

Licensed under GPL 2.0+