Database Design for Mere Mortals: A Hands-On Guide to Relational Database Design

Why is terminology important?

Terminology is important for the following reasons:

1. It is used to express and define the special ideas and concepts of the relational database model.

2. It is used to express and define the database-design process itself.

3. It is used anywhere a relational database or RDBMS is discussed.

Name the four categories of terms.

The four categories of terms are value- related , structure-related , relationship-related , and integrity-related .

What is the difference between data and information ?

The values you store in the database are data . Information is data that you process in a manner that makes it meaningful and useful to you when you work with it or view it.

What does a null represent?

A null represents a missing or unknown value.

What is a null's major disadvantage ?

The major disadvantage of nulls is that they have an adverse affect on mathematical operations.

What are the chief structures in the database?

Tables are the chief structures in the database.

Name the three types of tables.

The three types of tables are data tables, linking tables, and validation tables.

What is a view ?

A view is a virtual table composed of fields from one or more base tables in the database.

State the difference between a key and an index .

A key is a logical structure that you use to identify records within a table, and an index is a physical structure that you use to optimize data processing.

What are the three types of relationships that can exist between a pair of tables?

The three types of relationships that can exist between a pair of tables are one-to-one , one-to-many , and many-to-many .

What are the three ways in which you can characterize a relationship?

You can characterize every relationship in three ways: by the type of relationship that exists between the tables, the manner in which each table participates, and the degree to which each table participates.

What is a field specification ?

A field specification represents all the elements of a field.

What three types of elements does a field specification incorporate ?

A field specification incorporates three types of elements: general , physical , and logical .

What is data integrity ?

Data integrity refers to the validity, consistency, and accuracy of the data in a database.

Name the four types of data integrity.

The four types of data integrity are field-level , table-level , relationship-level , and business rules .