Vineet Chaoji wrote:

  Hi,

> So the query that I am trying to represent is:
Is there a Book
> "Book1" that has a chapter 'c1' that cites some article 'a'
and
> does this article 'a' have a chapter 'c2' which has a section
> 's'
which has a figure 'f' which is called "Example semi-joins".
> This is a
binary yes/no type of query.

  Given that $dblp is bound to the element DBLP,
the following
expression should return what you are looking for, and is I
think
self-explanatory:

    exists(
      $dblp
        /Book[@rdf:about eq
'Book1']
        /chapter
        /Chapter[@rdf:about eq 'c1']
/section
        /Section
        /cites[@rdf:resource eq 'a']
/../../../../../..
        /Article[@rdf:about eq 'a']
        /chapter
/Chapter[@rdf:about eq 'c2']
        /section
        /Section[@rdf:about eq
's']
        /figure[. eq '"Example Semi-join"']
    )

  Regards,

--
Florent Georges
http://fgeorges.org/