Create the list of all professors who ever taught MAT123. The information must include all attributes available from the Professor relation.

Using the document structure described in Exercise 15.23, formulate the following queries in XQuery:

{

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

     WHERE doc("http://xyz.edu/teaching.xml")

                                        //tuple[ProfId/@value=$p/Id/@value

                                                    and CrsCode/@value="MAT123"]

     RETURN $p

}