From http://www.w3schools.com (Copyright Refsnes Data)
RDF containers are used to describe group of things. For example, to list the authors of a book or to list the members in a band.
The following RDF elements are used to describe such groups: <Bag>, <Seq>, and <Alt>.
The <rdf:Bag> element is used to describe a list of values that is intended to be unordered.
The <rdf:Bag> element may contain duplicate values.
<?xml version="1.0"?> <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:cd="http://www.recshop.fake/cd#"> <rdf:Description rdf:about="http://www.recshop.fake/cd/Beatles"> <cd:artist> <rdf:Bag> <rdf:li>John</rdf:li> <rdf:li>Paul</rdf:li> <rdf:li>George</rdf:li> <rdf:li>Ringo</rdf:li> </rdf:Bag> </cd:artist> </rdf:Description> </rdf:RDF> |
The <rdf:Seq> element is used to describe a list of values that is intended to be ordered (For example, in alphabetical order).
The <rdf:Seq> element may contain duplicate values.
<?xml version="1.0"?> <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:cd="http://www.recshop.fake/cd#"> <rdf:Description rdf:about="http://www.recshop.fake/cd/Beatles"> <cd:artist> <rdf:Seq> <rdf:li>George</rdf:li> <rdf:li>John</rdf:li> <rdf:li>Paul</rdf:li> <rdf:li>Ringo</rdf:li> </rdf:Seq> </cd:artist> </rdf:Description> </rdf:RDF> |
The <rdf:Alt> element is used to describe a list of alternative values (the user can select only one of the values).
<?xml version="1.0"?> <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:cd="http://www.recshop.fake/cd#"> <rdf:Description rdf:about="http://www.recshop.fake/cd/Beatles"> <cd:format> <rdf:Alt> <rdf:li>CD</rdf:li> <rdf:li>Record</rdf:li> <rdf:li>Tape</rdf:li> </rdf:Alt> </cd:format> </rdf:Description> </rdf:RDF> |
In the examples above we have talked about "list of values" when describing the container elements. In RDF these "list of values" are called members.
So, we have the following:
From http://www.w3schools.com (Copyright Refsnes Data)