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SPARQL Scriptsยค

By prepending a Shebang line to a SPARQL query file and making the file executable, it can be treated as an executable script. To give an example, below is a simple text file with a generic SPARQL query that counts all triples in all graphs and outputs an ordered list.

count-graphs.sh
SELECT DISTINCT ?graph (COUNT(?graph) AS ?triples)
WHERE {
    GRAPH ?graph
    {
        ?s ?p ?o
    }
}
GROUP BY ?graph
ORDER BY DESC(?triples)

In order to convert this text file into a SPARQL script you need to add the following line to the top of the file:

shebang line for SPARQL scripts
#!/usr/bin/env -S cmemc query execute --accept text/csv

This will set cmemc as an interpreter for the rest of the file, and by using the query execute command, the rest of the file will be used as a SPARQL query.

Now you need to define your SPARQL file as executable and run it:

$ chmod a+x ./count-graphs.sh

$ ./count-graphs.sh
graph,triples
https://vocab.eccenca.com/shacl/,1796
https://vocab.eccenca.com/dsm/,736
https://vocab.eccenca.com/sketch/,395
https://ns.eccenca.com/example/data/dataset/,233
https://ns.eccenca.com/example/data/vocabs/,128
urn:elds-backend-access-conditions-graph,97
https://ns.eccenca.com/data/queries/,32
http://di.eccenca.com/project/cmem,7

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