data models

Question 1

focuses on how the database structure will be used to store and manage end-user data

Answer 1

database design

Question 2

the first step in designing a database

Answer 2

data modeling

Question 3

the process of creating a specific data model for a determined problem domain

Answer 3

data modeling

Question 4

a relatively simple representation, usually graphical, of more real-world data structures.

Answer 4

data model

Question 5

an abstraction of a more complex real-world object or event

Answer 5

model

Question 6

building blocks for data model:

Answer 6

• entity
• attribute
• relationship

Question 7

a person, place, thing or event about which data will be collected and stored

Answer 7

entity

Question 8

a characteristic of an entity

Answer 8

attribute

Question 9

describes an association among entities

Answer 9

relationship

Question 10

three types of relationships:

Answer 10

• one-to-one (1:1) relationship
• one-to-many (1:M) relationship
• many-to-many (M:M) relationship

Question 11

this model’s basic logical structure is represented by an upside-down tree.

it contains levels or segments

segments is the equivalent of a file system’s record type

developed in the 1960’s to manage large amounts of data for complex manufacturing projects

Answer 11

hierarchical model

Question 12

data model that was created to represent complex data relationships to improve database performance and to impose database standard

Answer 12

network model

Question 13

it is the conceptual organization of the entire database

Answer 13

schema

Question 14

it defines the portion of the database by the application programs that actually produce the desired info from the data in the database

Answer 14

subschema

Question 15

it defines the environment in which data can be managed

Answer 15

data manipulation language (DML)

Question 16

it allows the database administrator to define the schema components

Answer 16

data definition language (DDL)

Question 17

data model that was introduced in 1970 by E. F. Codd of IBM, represented a major breakthrough for both users and designers

relation - foundation of mathematical concept

Answer 17

relational model

Question 18

data model that was introduced in 1976 by peter chen

Answer 18

entity relationship model

Question 19

a metalanguage used to represent and manipulate data elements.

Answer 19

extensible markup language (XML)

Question 20

it refers to a movement to find new and better ways to manage large amounts of web and sensor-generated data and derive business insight from it

Answer 20

big data

Question 21

the basic characteristics of big data databases that was described by Douglas Laney, a data analyst from the Gartner Group:

Answer 21

volume, velocity, variety

Question 22

it refers to the amounts of data being stored

Answer 22

volume

Question 23

it refers not only to the speed with which data grows but also to the need to process this data quickly in order to generate information and insight

Answer 23

velocity

Question 24

it refers to the fact that the data being collected comes in multiple different data formats

Answer 24

variety

Question 25

it is a large-scale distributed database system that store structured and unstructured data in efficient ways

Answer 25

noSQL

Question 26

general characteristics of noSQL databases:

Answer 26

- they are not based on the relational model and SQL - they support distributed database architectures - they provide high-scalability, high availability, and fault tolerance - they support very large amounts of sparse data - they are geared toward performance rather than transaction consistency

Question 27

advantages of noSQL:

Answer 27

- noSQL supports distributed database architecture - noSQL supports very large amounts of sparse data - noSQL provides high scalability, high availability, and fault tolerance - most noSQL databases are geared toward performance rather than transactions consistency

Question 28

in 1970's, they defined a framework for data modeling based on degrees of data abstraction.

Answer 28

american national standards institute (ANSI) standards planning and requirements committee (SPARC)

Question 29

the resulting ANSI/SPARC architecture defines three levels of data abstraction:

Answer 29

external, conceptual, and internal

Question 30

it is the end user's view of the data environment

Answer 30

external model

Question 31

it represents a global view of the entire database by the entire organization

Answer 31

conceptual model

Question 32

it is the representation of the database as "seen" by the DBMS

Answer 32

internal model

Question 33

depicts a specific representation of an internal model, using the database constructs supported by the chosen database

Answer 33

internal schema

Question 34

operates at the lowest level of abstraction, describing the way data is saved on storage media such as magnetic, solid stage, or optical media.

Answer 34

physical model