Answers to Chapter 16 Review Questions
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1. A record is a collection of unordered, heterogeneous values that
   has conceptual integrity as a single unit: a field is any of the
   values that make up that collection.  C programmers often refer to
   these concepts as structures and members, respectively.

2. True

3. False, the types of each field in a record can be different, but
   need not be.

4. Before you declare a record variable, you must first define a new
   structure type representing the record.  After doing so, you can
   then declare variables of that new type.

5. The . operator (pronounced dot) is used to select a field from a
   record.

6. True

7. True

8. Cratchit's salary: staff[1].salary
   Scrooge's first initial: staff[0].name[0]

10. The three factors that influence the decision as whether a type
    should be declared as a record or as a pointer to a record are:
    - The size of the record type
    - The cost of memory allocation
    - The discipline used by functions that manipulate that type

12. The expression *p.cost has the wrong operator precedence to
    achieve the desired effect.  As written, the dot operator is
    applied first, followed by the asterisk; what you ordinarily want
    is to have these operators applied in the opposite order.  To
    simplify this combined operation of dereference and selection, C
    provides the -> operator, which is illustrated by the expression
    p->cost

13. A database is a large collection of structured objects that can be
    maintained in permanent storage.

14. The external representation of the database allows it to be stored
    in a file system, which is often limited to ASCII text.  For more
    convenient manipulation, however, you also need to design an
    internal representation that can be manipulated directly by the
    program.  To design the external database, programmers must
    consider the limitations of the file storage medium and the extent
    to which the database should be readable by humans.  For the
    internal database, the design is driven by the types of operations
    that the program needs to perform.

16. The term data-driven design refers to programs that control their
    entire operation on the basis of information from a database.
    Data-driven programs are usually shorter, more flexible, and
    easier to maintain than programs that incorporate the same
    information directly into the implementation.