Chapter 3: The Relational Database Model

Question 1

the column’s range of permissible values

Answer 1

domain

Question 2

is an attribute or combination of attributes that uniquely identifies any given row

Answer 2

primary key

Question 3

consists of one or more attributes that determine other attributes

Answer 3

key

Question 4

the state in which knowing the value of one attribute makes it possible to determine the value of another

Answer 4

determination

Question 5

the value of one or more attributes determines that the value of one or more attributes determine the value of one or more other attributes.

Answer 5

functional dependence

Question 6

the attribute whose value determines another

Answer 6

determinant

Question 7

the attribute whose value is determined by the other attribute

Answer 7

dependent

Question 8

used to refer functional dependencies in which the entire collection of attributes in the determinant is necessary for the relationships

Answer 8

full functional dependence

Question 9

a key that is composed of more than one attribute

Answer 9

composite key

Question 10

an attribute that is a part of a key

Answer 10

key attribute

Question 11

a key that can uniquely identify any row in the table

Answer 11

superkey

Question 12

a minimal superkey- that is a superkey without any unnecessary attributes

Answer 12

candidate key

Question 13

the condition in which each row in the table has its own unique identity

Answer 13

entity integrity

Question 14

the absence of any data value and it is never allowed in any part of the primary key

Answer 14

null

Question 15

the primary key of one table that has been placed into another table to create a common attribute

Answer 15

foreign key (FK)

Question 16

the condition in which every reference to an entity instance by another entity instance is valid

Answer 16

referential integrity

Question 17

a key that is used strictly for data retrieval purposes

Answer 17

secondary key

Question 18

involved when a table record is considered for deletion

Answer 18

delete rules

Question 19

apply when a new record is about to be inserted into a table

Answer 19

insert rules

Question 20

apply when an existing record is about to be updated

Answer 20

update rules

Question 21

rule that states if an attempt is made to delete a record in one table where on or more records with matching foreign key values exist in another table, all associated records will be deleted

Answer 21

cascade delete rule

Question 22

rule that states that if an attempt is made to delete a record in one table where one or more records with matching foreign key values exist in another table, that the delete operation will not be allowed

Answer 22

restrict delete rule

Question 23

rule that states if an attempt is made to delete a record in one table where one or more records with matching foreign key values exist in another table, then the foreign key values are set to NULL so we know that the record they used to point to has been deleted

Answer 23

set-to- null delete rule

Question 24

all primary key entries are unique, and no part of a primary key may be null

Answer 24

requirement of entity integrity

Question 25

a special code to avoid nulls to indicate the absence of some value

Answer 25

flag

Question 26

an orderly arrangement used to logically access rows in a table

Answer 26

index

Question 27

the index’s reference point

Answer 27

index key

Question 28

the index key can have only one pointer value

Answer 28

unique index