Create a document that lists every course and the professors who taught it. The course information must include the course name, and the professor information should include the professor’s name.

Use the document structure described in Exercise 15.23 to formulate the following queries in XQuery:

{

     FOR $c IN doc("http://xyz.edu/courses.xml")//tuple

     LET $tch := doc("http://xyz.edu/teaching.xml")

                                         //tuple[CrsCode/@value=$c/CrsCode/@value]

     LET $profs := {

     FOR $t IN $tch,

             $p IN doc("http://xyz.edu/professor.xml")

                                             //tuple[Id/@value=$t/ProfId/@value]

                   }

RETURN

         

                  $c/CrsName

                  {

                          FOR $p IN distinct-values($profs)

                          RETURN  $p/Name 

                   }

          

}