Understands how to combine and filter graph patterns using operators such as UNION, OPTIONAL, FILTER, and MINUS. – Linked Data for Professional Education

0 to 60 on SPARQL Queries in 50 Minutes

Sun, 06 May 2018 02:22:48 +0000

This webinar provides an introduction to SPARQL, a query language for RDF. Users will gain hands on experience crafting queries, starting simply, but evolving in complexity. These queries will focus on coinage data in the SPARQL endpoint hosted by http://nomisma.org with numismatic concepts defined in a SKOS-based thesaurus and physical specimens from three major museum collections (American Numismatic Society, British Museum, and Münzkabinett of the Staatliche Museen zu Berlin) linked to these concepts. Results generated from these queries in the form of CSV may be imported directly into Google Fusion Tables for immediate visualization in the form of charts and maps. Links to all resources necessary to practice the queries covered are available online and referenced from the webinar presentation.

The webinar uses the following SPARQL constructs: SELECT, WHERE, LIMIT, ORDER BY (ASC), FILTER, DISTINCT, regex(), count(), lang(), langMatches().

Access to all SPARQL queries used in the webinar are available at http://numishare.blogspot.com/2015_05_01_archive.

URL: https://www.asist.org/events/webinars/dcmi-webinar-from-0-to-60-on-sparql-queries-in-50-minutes/
Keywords: visualization (map geolocations), Google Fusion Tables, visualization (statistics), geographic queries, UNION, OPTIONAL, sorting, filtering, SPARQL syntax
Author: Ethan Gruber
Publisher: DCMI
Date created: 2014-01-01 07:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P1H00M
Educational use: instruction
Educational audience: student
Interactivity type: mixed

Equality and Inequality in SPARQL

Sun, 13 Aug 2017 08:18:11 +0000

This brief blog post discusses issues surrounding expression semantics in SPARQL. Practices that people are used to from other languages (like the use of "=" and "!="), can often be confusing to new – and even not so new- SPARQL developers. The author suggests that an awareness of type errors will allow the user to understand what is occurring. Example queries show how type errors are treated when using FILTER. An alternative method involving project expressions or BIND is proposed.

URL: http://www.cray.com/blog/equality-inequality-sparql/
Keywords: SPARQL, BIND, FILTER, Type errors, Project expressions
Author: Vesse, Rob
Publisher: Cray
Date created: 2013-04-23 04:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P10M
Educational use: instruction
Educational audience: student
Interactivity type: expositive

Jena Full Text Search

Sun, 13 Aug 2017 08:18:11 +0000

This documentation explains how to configure and use the Full Text extension to Apache Jena's ARQ (the module is included in Fuseki). The extension combines SPARQL and full-text search via Lucene or ElasticSearch (built on Lucene). It gives applications the ability to perform indexed full-text searches within SPARQL queries. Although SPARQL allows the use of regular expressions in FILTER, this is a test on a value retrieved earlier in the query and its use is not indexed. In other words, if you're searching for occurrences of a specific term in the rdfs:label of a bunch of products, then the search will need to examine all selected rdfs:label statements and apply the regular expression to each label in turn. If there are many such statements and many such uses of regex, then it may be appropriate to consider using this extension to take advantage of the performance potential of full text indexing.

URL: http://jena.apache.org/documentation/query/text-query.html
Keywords: SPARQL, REGEX, FILTER, Apache Jena
Publisher: Apache Jena
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P2H
Educational use: professionalDevelopment

SPARQL and Linked Data Homework Exercises

Sat, 21 Jan 2017 06:46:40 +0000

This document contains several "written" and "electronic" homework questions originally from the course "Semantic Web Topics" at LeHigh University. They include: Write a series of SPARQL queries using a provided schema; Write a SPARQL construct query that generates all triples inferred by a specific RDFS entailment rule; Write a SPARQL construct query to generate
owl:sameAs statements between domains which share specified property; Describe the pros and cons of generating links in the manner specified in the previous question; Using Jena, create a class that can read in all the files in a specified directory and create a Web page that lists a series of publications organized by topic – reading all of the files into a single model and only using SPARQL to retrieve information from the model.

URL: http://www.cse.lehigh.edu/~heflin/courses/sw-2013/hw2.pdf
Keywords: SPARQL, RDF Schema, Entailment regime, Apache Jena, Java
Author: Heflin, Jeff
Date created: 2013-02-01 05:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P4H
Educational use: assessment
Educational audience: teacher-educationSpecialist
Interactivity type: active

Ordnance Survey Linked Data: Combining Postcode and Spatial Queries

Mon, 16 Jan 2017 06:46:07 +0000

Building on previous blog posts, the author shows how to query and combine data from two different datasets. Although the datasets were published by the same organization, they are in two different file formats (CSV and shape). The two datasets are, however, implicitly linked via a key. By converting both datasets into a common data language (RDF), those implicit links can be made explicit, allowing the user to easily query both datasets together.

URL: https://johngoodwin225.wordpress.com/2013/08/05/ordnance-survey-linked-data-combining-postcode-and-spatial-queries/
Keywords: SPARQL, Linked Open Data (LOD), Government Open Data
Author: Goodwin, John
Date created: 2013-08-05 04:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P20M
Educational use: instruction

Ordnance Survey Linked Data: A Simple Postcode Query

Mon, 16 Jan 2017 06:46:07 +0000

This blog post shares give some simple examples of what can be done with the Code-Point(R) Open dataset, available as Linked Open Data (LOD). This dataset has a URI for every Postcode Unit, Postcode Sector, Postcode District and Postcode Area in England, Scotland and Wales. Includes example SPARQL queries and also serves as a brief exercise in how to find the URIs of particular resources within a dataset and determine which predicates describe important relationships between those resources. These skills are necessary to form SPARQL queries.

URL: https://johngoodwin225.wordpress.com/2013/08/05/ordnance-survey-linked-data-a-simple-postcode-query/
Keywords: Linked Open Data (LOD), SPARQL
Author: Goodwin, John
Date created: 2013-08-05 04:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P15M
Educational use: professionalDevelopment
Educational audience: student
Interactivity type: expositive

Ordnance Survey Linked Data: Simple SPARQL Example

Mon, 16 Jan 2017 06:46:07 +0000

This blog post shares how to retrieve several variables of data from the Ordnance Survey dataset, available as Linked Open Data (LOD). Includes SPARQL queries and instructions on how to retrieve the desired output format from the SPARQL endpoint.

URL: https://johngoodwin225.wordpress.com/2013/08/01/ordnance-survey-linked-data-simple-sparql-example/
Keywords: Linked Open Data (LOD), SPARQL
Author: Goodwin, John
Date created: 2013-08-01 04:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P15M
Educational use: instruction
Educational audience: student
Interactivity type: expositive

SPARQL: Using Operators Tutorial and Quiz

Thu, 24 Nov 2016 05:51:17 +0000

This slide tutorial focuses on using various operators in SPARQL queries. Several examples are provided which include the RDF data being queried, the SPARQL query itself, and the result table. This is followed by quiz questions which ask the user to query DBpedia's SPARQL endpoint. The answers to the question (in the form of completed SPARQL queries) are included.

URL: http://skkudatalab.weebly.com/sparql-operators.html
Keywords: DBpedia, SPARQL
Author: Oh, Sam
Publisher: Sungkyunkwan University (SKKU)
Date created: 2016-11-22 05:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P40M
Educational use: instruction
Educational audience: professional
Interactivity type: expositive

SPARQL: Using DESCRIBE and CONSTRUCT Tutorial and Quiz

Thu, 24 Nov 2016 05:51:17 +0000

This slide tutorial focuses on using DESCRIBE and CONSTRUCT in SPARQL queries, but also includes other basic operators. Several examples are provided which include the RDF data being queried, the SPARQL query itself, and the result table. This is followed by quiz questions which ask the user to query DBpedia's SPARQL endpoint. The answers to the question (in the form of completed SPARQL queries) are included.

URL: http://skkudatalab.weebly.com/sparql-describe.html
Keywords: DBpedia, SPARQL
Author: Oh, Sam
Publisher: Sungkyunkwan University (SKKU)
Date created: 2016-11-22 05:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P20M
Educational use: instruction
Educational audience: professional
Interactivity type: expositive

SPARQL: Using ASK Tutorial and Quiz

Thu, 24 Nov 2016 05:51:17 +0000

This slide tutorial focuses on using ASK in SPARQL queries, but also includes other basic operators. Several examples are provided which include the RDF data being queried, the SPARQL query itself, and the result table. This is followed by quiz questions which ask the user to query DBpedia's SPARQL endpoint. The answers to the question (in the form of completed SPARQL queries) are included.

URL: http://skkudatalab.weebly.com/sparql-ask.html
Keywords: SPARQL, DBpedia
Author: Kim, Seonghun
Publisher: Sungkyunkwan University (SKKU)
Date created: 2016-11-22 05:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P20M
Educational use: instruction
Educational audience: teacher-educationSpecialist
Interactivity type: mixed