12.1 What are the origins of the object-oriented approach?

12.7 What is the difference between persistent and transient objects? How is persistence handled in typical OO database systems?

12.21 What is meant by the type orthogonality of OQL?

Chapter 13 #

13.3 

What are the differences between the use of tags in XML versus HTML?

13.4.

What is the difference between data-centric and document-centric XML documents?

Chapter 14 #

14.3  Why should NULLs in a relation be avoided as much as possible? Discuss the problem of spurious tuples and how we may prevent it.

Chapter 15 #

15.2  What is meant by the completeness and soundness of Armstrong’s inference rules?

15.7 Why are normal forms alone insufficient as a condition for a good schema design?