Retrieve all resources with same RDF/XML element name without using ID

Question

Printing subjects of all my graph Triples, I saw that subjects in my data are are always URIs of the form GraphURI/#SubjectID. I'm able to retrieve the properties and values of one subject with a query like:

SELECT ?predicate ?object
WHERE {
  <GraphURI/#SubjectID> ?predicate ?object
} 

I would like to do this for all the resources that are represented by cim:ACLineSegment elements in the RDF/XML serialization, though. This is what the serialization looks like:

<cim:ACLineSegment rdf:ID="_05b8">
    <!-- some code... -->
</cim:ACLineSegment>
    <!-- other blocks -->
<cim:ACLineSegment rdf:ID="_05b9">
    <!-- some code... -->
</cim:ACLineSegment>

I would like something like the following. Is this possible?

SELECT ?predicate ?object
WHERE {
  cim:ACLineSegment ?predicate ?object
}

Answer 1

My problem is that I would like to retrieve all subjects containing cim:ACLineSegment, whatever the ID they may have.

<cim:ACLineSegment rdf:ID="_05b8">
    <!-- some code... -->
</cim:ACLineSegment>

Your subjects don't “contain” cim:ACLineSegment. Subjects don't contain anything in RDF. Resources (including subjects of triples) are identified by URIs. RDF is based on triples of the form {subject, predicate, object}. The snippet you're showing is RDF/XML, which is a particular serialization of triples. In the snippet you've shown, there are some triples of the form {<.../_05b8>, rdf:type, cim:ACLineSegment}. That is, your subjects have the value cim:ACLineSegment as the value of the rdf:type property.

To explain a little bit more, suppose you had the following data. (By the way, in the future, it will be much more helpful if you provide minimal, but complete, sample data. The data you provided isn't complete, and we can't run queries against it, and we can't be sure what it is in context.)

<rdf:RDF
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns:ex="http://stackoverflow.com/q/23432445/1281433/ex#"
    xml:base="http://stackoverflow.com/q/23432445/1281433/ex#">
  <ex:Person rdf:ID="Mary">
    <ex:hasName>Mary</ex:hasName>
  </ex:Person>
  <ex:Person rdf:ID="Jim">
    <ex:hasName>James</ex:hasName>
    <ex:hasAge rdf:datatype="http://www.w3.org/2001/XMLSchema#integer">34</ex:hasAge>
  </ex:Person>
  <ex:Person rdf:ID="John">
    <ex:hasName>John</ex:hasName>
  </ex:Person>
</rdf:RDF>

If you take a look at this data in the N-Triples serialization (which has just one triple per line), you'll see these triples:

<http://stackoverflow.com/q/23432445/1281433/ex#Mary> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://stackoverflow.com/q/23432445/1281433/ex#Person> .
<http://stackoverflow.com/q/23432445/1281433/ex#Mary> <http://stackoverflow.com/q/23432445/1281433/ex#hasName> "Mary" .
<http://stackoverflow.com/q/23432445/1281433/ex#John> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://stackoverflow.com/q/23432445/1281433/ex#Person> .
<http://stackoverflow.com/q/23432445/1281433/ex#John> <http://stackoverflow.com/q/23432445/1281433/ex#hasName> "John" .
<http://stackoverflow.com/q/23432445/1281433/ex#Jim> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://stackoverflow.com/q/23432445/1281433/ex#Person> .
<http://stackoverflow.com/q/23432445/1281433/ex#Jim> <http://stackoverflow.com/q/23432445/1281433/ex#hasName> "James" .
<http://stackoverflow.com/q/23432445/1281433/ex#Jim> <http://stackoverflow.com/q/23432445/1281433/ex#hasAge> "34"^^<http://www.w3.org/2001/XMLSchema#integer> .

Notice all those rdf:type triples? That's because in RDF/XML syntax (§2.13 Typed Node Elements), an element that corresponds to a resource, has the element name as a value for rdf:type. Thus, the RDF/XML above is actually shorthand for this data:

<rdf:RDF
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns:ex="http://stackoverflow.com/q/23432445/1281433/ex#" > 
  <rdf:Description rdf:about="http://stackoverflow.com/q/23432445/1281433/ex#Mary">
    <rdf:type rdf:resource="http://stackoverflow.com/q/23432445/1281433/ex#Person"/>
    <ex:hasName>Mary</ex:hasName>
  </rdf:Description>
  <rdf:Description rdf:about="http://stackoverflow.com/q/23432445/1281433/ex#Jim">
    <rdf:type rdf:resource="http://stackoverflow.com/q/23432445/1281433/ex#Person"/>
    <ex:hasName>James</ex:hasName>
    <ex:hasAge rdf:datatype="http://www.w3.org/2001/XMLSchema#integer">34</ex:hasAge>
  </rdf:Description>
  <rdf:Description rdf:about="http://stackoverflow.com/q/23432445/1281433/ex#John">
    <rdf:type rdf:resource="http://stackoverflow.com/q/23432445/1281433/ex#Person"/>
    <ex:hasName>John</ex:hasName>
  </rdf:Description>
</rdf:RDF>

It's also helpful to view the data in N3 or Turtle syntax, because it's much closer to the SPARQL query syntax:

@prefix ex:    <http://stackoverflow.com/q/23432445/1281433/ex#> .
@prefix rdf:   <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .

ex:Mary  a          ex:Person ;
        ex:hasName  "Mary" .

ex:John  a          ex:Person ;
        ex:hasName  "John" .

ex:Jim  a           ex:Person ;
        ex:hasAge   34 ;
        ex:hasName  "James" .

What all of this means is that you simply want to ask for things with a specified type. Your query would be:

select ?predicate ?object where {
  ?subject rdf:type cim:ACLineSegment ;     # You can use `a` instead of rdf:type.
           ?predicate ?object
}