querying RDFs using SPARQL query - sql

Question

Assuming we have a dataset including the following 3 RDF triples. I want to retrieve all these three triples using sparql query.
http://test.com/11/META_C1-INST predicate1 http://test.com/NO_CONTEXT/META_C0059714-INST
http://test.com/23/META_C1-INST predicate1 http://test.com/NO_CONTEXT/META_C0059714-INST
http://test.com/43/META_C1-INST predicate1 http://test.com/NO_CONTEXT/META_C0142817-INST
Here is the query I wrote but I know it is not right:
prefix pred:<http://test.com/>
select distinct *
where {pred:META_C1-INST ?p ?o};
How should I say: "Look for any triples with the subject from http://test.com/??/ where ?? can be anything like 11, 23, S23?

Answer 1

You can transform the URI into a string and then filter based on what it starts with. The keyword you need to use is STRSTARTS:
select distinct *
where{
?s ?p ?o
filter(STRSTARTS(str(?s), "http://test.com/"))
}
or you can use regular expressions with the ^ sign:
select distinct *
where{
?s ?p ?o
FILTER regex(str(?s), "^http://test.com/") .
}