random

Question 1

made by E. F. Codd in 1970

Answer 1

relational model

Question 2

framework where assertion can be true or false

Answer 2

predicate logic

Question 3

also known as statement of fact

Answer 3

assertion

Question 4

sets or groups of things used as a basis for data manipulation

Answer 4

set theory

Question 5

components of relational model

Answer 5

logical data structure
set of integrity rules
set of operations

Question 6

two-dimensional structure with rows and columns

Answer 6

table (relation)

Question 7

table is also known as what?

Answer 7

relation

Question 8

this are data about an entity

Answer 8

row

Question 9

rows are also known as what?

Answer 9

tuple

Question 10

these are attributes of an entity

Answer 10

column

Question 11

these are specific range of values

Answer 11

domain

Question 12

determines the values of other attributes

Answer 12

key

Question 13

knowing the value of an attribute to determine the value of another attribute

Answer 13

determination

Question 14

the value of attributes determines the value of other attributes

Answer 14

functional dependence

Question 15

attribute whose value determines another

Answer 15

determinant

Question 16

attribute whose value is determined by the other attribute

Answer 16

dependent

Question 17

key composed of more than one attribute

Answer 17

composite key

Question 18

attribute that is part of a key

Answer 18

key attribute

Question 19

attribute that identifies any row in the table

Answer 19

superkey

Question 20

superkey without any unnecessary attributes

Answer 20

candidate key

Question 21

candidate key that identifies other attribute values in any given row

Answer 21

primary key

Question 22

attribute in one table whose values must either match the primary key or be null

Answer 22

foreign key

Question 23

attribute used for data retrieval purposes

Answer 23

secondary key

Question 24

these are followed to maintain a good database design

Answer 24

integrity rules

Question 25

each row in a table has its own unique identity

Answer 25

entity integrity

Question 26

reference to an entity instance by another entity instance is valid

Answer 26

referential integrity

Question 27

special codes to indicate the absence of some value

Answer 27

flags

Question 28

mathematical principles that form the basics for manipulating relational table contents

Answer 28

relational algebra

Question 29

the use of relational algebra operators on existing table, produces new relations

Answer 29

closure

Question 30

the condition to be evaluated

Answer 30

predicate

Question 31

retrieves the subsets of rows

Answer 31

select

Question 32

retrieves subset of columns

Answer 32

project

Question 33

merges two union-compatible tables into a new table

Answer 33

union

Question 34

retrieves rows that are common to two union-compatible tables

Answer 34

interset

Question 35

retrieves rows from one table that are not found in another

Answer 35

difference

Question 36

retrieves possible pairs of rows fron two tables

Answer 36

product

Question 37

product operation is also called as what

Answer 37

cartesian product

Question 38

retrieves rows from two tables based on criteria

Answer 38

join

Question 39

retrieves values

Answer 39

divide

Question 41

describes relationships among entities at the conceptual level

Answer 41

entity relationship model (ERM)

Question 42

depicts an EDM's entities, attributes, and relations

Answer 42

entity relationship diagram (ERD)

Question 43

each row in the rlational table

Answer 43

entity instance or entity occurrence

Question 45

collection of similar entities

Answer 45

entity set

Question 46

describes associations among data

Answer 46

relationships

Question 47

type of relationships between entities; represented by a line

Answer 47

connectivity

Question 48

ER Model Notations

Answer 48

chen notation crow's feet notation