Comp 2: Relational Databases

Question 1

What is a DB model?

Answer 1

Conceptual framework for a DB.

Question 2

What were the leading DB models in the 1960s?

Answer 2

hierarchic and network

Question 3

Who was the original creator of the relational model?

Answer 3

E.F Codd

Question 4

What are primary examples of a Hierarchical, Network, Relational, and NoSQL DBS?

Answer 4

Hierarchical: IMS
Network: IDMS
Relational: MySQL, Oracle, SQL Server
NoSQL models: MongoDB, Redis, Cassandra, Neo4j

Question 5

Why were relational DBs not used right away?

Answer 5

processing speeds sucked

Question 6

What are three parts of the relational model?

Answer 6

1. Data structure that says how data is organized.

Question 7

What is the difference between a domain, tuple, and relation?

Answer 7

Domain: Data Type
Tuple: Row
Relational: Table

Question 8

How do attributes relate to tuples?

Answer 8

Attribute is name for each tuple position. Basically, column headers.

Question 9

What are 7 relational operations?

Answer 9

SELECT, project, product, JOIN, UNION, INTERSECT, difference

Question 10

What are relational (or integrity) rules?

Answer 10

logical constraints that make sure data is valid

Question 11

What are structural rules?

Answer 11

Relational rules that are present in every relational DB.

Question 12

Give 3 examples of structural rules

Answer 12

Unique Primary Key, Unique Column Names, No duplicate rows.

Question 13

What are business rules?

Answer 13

relational rules specific to a particular DB.