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CSE 344 -- Spring 2011
Lecture 14:   Midterm Review and Discussion of Mapping XML to Relations

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Midterm:

   -- Friday, 9:30, in class

   -- closed book

   -- Four problems:

       1. SQL/Relational-calculus/Datalog
       2. Relational Algebra
       3. XML/XPath/XQuery
       4. E/R Diagrams

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Today: 

  finish discussion of E/R diagrams, 
 
  mapping XML to relations

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Suppose we have XML documents conforming to this DTD:

<!DOCTYPE bib [
	<!ELEMENT bib  (book* )>
	<!ELEMENT book  (title,  (author+ | editor+ ), publisher?, price )>
	<!ATTLIST book  year CDATA  #REQUIRED >
	<!ELEMENT author  (last, first )>
	<!ELEMENT editor  (last, first, affiliation )>
	<!ELEMENT title  (#PCDATA )>
	<!ELEMENT last  (#PCDATA )>
	<!ELEMENT first  (#PCDATA )>
	<!ELEMENT affiliation  (#PCDATA )>
	<!ELEMENT publisher  (#PCDATA )>
	<!ELEMENT price  (#PCDATA )>
]>


****  In Class: design an E/R Diagram, design relations

****  In Class: Translate the following  XPath expressions to SQL

XPath = /bib/book[author[last="Ullman"][first="Jeff"]]
SQL   = ?

XPath = /bib/book[author/last="Ullman"][author/first="Jeff"]
SQL   = ?

**** In class: Suppose we want to design a relational schema that can
     store ANY XML document.  How do we do this ?  Now translate the
     queries above to SQL.

[This problem will be continued in the sections on Thursday]