relational database model

Question 1

key characteristics of relational model

Answer 1

-views data more logically than physically

• conceptual model
• data independent
• structure independent

Question 2

What are keys?

Answer 2

Keys consist of one or more attributes that determine other attributes

Question 3

full functional dependence

Answer 3

when entire collection of attributes in the determinant is necessary for the relationship.

Question 4

determinant and dependent

Answer 4

determinant –> dependent

Question 5

composite key

Answer 5

key which is composed of more than one attribute

Question 6

superkey

Answer 6

A key that uniquely identifies any row in a table

Question 7

candidate key

Answer 7

A minimal superkey. It is a superkey without any unnecessary attributes.

Question 8

primary key

Answer 8

A candidate key. (minimal superkey). Which is chose to the primary key of a table, to uniquely identify rows.

Question 9

Entity integrity

Answer 9

Each row in the table has its own identity

Question 10

Foreign key

Answer 10

A primary key of one table placed into another table to create a common attribute.

Question 11

referential integrity

Answer 11

every reference to an entity by another entity is valid.