Lecture 6: Data Management, Modeling and Manipulation

Question 1

What is data, information and knowledge?

Answer 1

Data - raw facts without deeper meaning

Information - data shaped into meaningful form through context

Knowledge - results from experience and education

Question 2

What is a relational database?

Answer 2

• It organizes data into one or more related tables
• Consist of columns and rows
• Unique primary key identifies each row

Question 3

How can redundancy’s improve database performance?

Answer 3

Join-operations become unnecessary

Question 4

What are the requirements of normal form 1?

Answer 4

1. The domain of each attribute contains only atomic values
2. Atomic values are values that cannot be split into multiple logically distinct parts
3. The value of each attribute only contains a single value form that domain

Question 5

What are the requirements of normal form 2?

Answer 5

1. It satisfies 2NF

2. In case there is a composite key, there is no partial dependencies

Question 6

What are the requirements of normal form 3?

Answer 6

1. It satisfies 3NF

2. There are no transitive dependence (attributes may not be functionally dependent on other non-key attributes)