itss 4300 module 4 review part 1

Question 1

Briefly, but precisely, explain the difference between single-valued attributes and simple attributes. Give an example of each.

Answer 1

A single -valued attribute is one that can have only one value. For example, a person has only one first name and only one social security number.

A simple attribute is one that cannot be decomposed into its component pieces. For example, a person’s sex is classified as either M or F and there is no reasonable way to decompose M or F.

Question 2

What three (often conflicting) database requirements must be addressed in database design?

Answer 2

Desing standards
processing speed
Information requirements

Question 3

An entity whose primary key is composed of multiple attributes.

In general, it is used to transform M:N relationships into 1:M relationships.

Answer 3

Composite entity

Question 4

A _______ relationship exists when the primary key of one entity becomes part of the primary key of another entity.

Answer 4

strong

Question 5

Describes an entity that has a relationship with itself.

Answer 5

recursive