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Further opportunities for study

We hope you’ve enjoyed this course! Are you interested in learning more about Linked Data, SPARQL, or the Semantic Web? Here we discuss a number of study and training opportunities. …

More real world applications

In step 1.15 you watched Dr Barry Norton describe some real world applications that have Linked Data as their underlying technology. In this step, we introduce you to some more …

Keep practising SPARQL!

To really get familiar with SPARQL, you should practise what you’ve learned so far. It’s not too late to get started with running SPARQL queries on the MusicBrainz dataset … …

Goodbye!

We hope that you have enjoyed your journey with us! We would like to remind you, that whilst we will not be providing facilitation in the comments and discussions after …

Reasoning over linked data

Reasoning enhances the information contained in a dataset by including results obtained by inference from the triples already present. As a simple example, suppose that the dataset includes the following …

Reasoning using RDFS

RDF Schema introduces a very limited range of logical terms based mostly on the concept of class, or rdfs:Class, a concept absent from RDF. It is possible to state directly …

Queries using DESCRIBE

Like CONSTRUCT, DESCRIBE delivers as output an RDF graph – i.e., a set of RDF triples. It differs from CONSTRUCT in that these triples are not constructed according to a …

Assigning variables

If you want to construct RDF triples using a variable that is derived from retrieved data, e.g., through an arithmetical operation, you can add a BIND statement to the WHERE …

Ordering and limiting triples

When building new RDF triples with CONSTRUCT, you can use the operators described in Step 2.10 (Ordering query results) in order to organise and delimit the variable bindings retrieved from …

Disjunction

Suppose that for some reason you want to construct triples for albums made either by the Beatles or by the Smashing Pumpkins (or both). Including both of these constraints in …

Missing information

In the examples we have seen so far, variable bindings must be retrieved for all patterns listed after WHERE. This means that if we retrieve several facts about an album …

Aggregate data

This step introduces one more operation to use with SELECT queries, before we move on to CONSTRUCT queries. If we want to report the total duration of an album, we …

Queries using CONSTRUCT

In this step, you will learn how CONSTRUCT queries return new RDF graphs. When building an application like the music portal, you might need to retrieve some information from a …