Leandra Mangieri
3/06/07
Post Lab Questions 3.2

1.  Alabama Virtual Library database (www.avl.lib.al.us) contains many databases; for example, the Gale
database stores information on articles, critical analyses, information about literary works, and information
about authors.

Cdnow.com, similar to Amazon.com, stores data about cd products, reviews, and other products.

2.  professor --(teaches)-->course
    professor--(teaches in)-->classroom
    professor--(belongs to)-->department
    course--(taught in)-->classroom
    course--(belongs to)-->department
    department--(contains)-->course

3.  The relationship between professor and course is 1 to many because the professor might teach more
than one course.  

The relationship between professor and classroom may be 1 to many also because the professor might teach
in more than 1 classroom.

The relationship between professor and department is 1 to 1 because the professor most likely belongs to
one department/

The relationship between course and classroom is many to many because many different courses are taught in
many different classrooms.

The relationship between course and department is many to one because all the different courses belong to only
1 department.

The relationship between department and course is one to many because a single department likely contains many
courses.

4.  Entities for a database keeping track of a radio station's record collection might include artist's name,
cd title, release year, record company, hit song, etc.


5.  In a database, tables are used to store all the information the database contains in tuples.  Queries, however,
do not hold data themselves.  Instead, they are used in ways to build new tables out of existing tables.  Queries
describe processes and actions, rather than describe information (which is what a table does).