5.2 database approach

Question 1

file management environment

Answer 1

original old timey way of data management

Question 2

data file

Answer 2

collection of logically related records

Question 3

what is the benefit of using a database?

Answer 3

eliminates many problems of old file maangemt systems

-> all users can access to al of the data
->reduce DATA REDUNDANCY!
->reduce DATA ISOLATION!
-> reduce DATA INCONSISTENCY!

Question 4

Data redundancy

Answer 4

the same data are stored in multiple locations

Question 5

Data Isolation

Answer 5

applications cant access data associated with other applications

Question 6

Data inconsistency

Answer 6

various copies of the data do not agree

Question 7

benefits of database systems?

Answer 7

1) data security
2) data integrity
3) data independance

Question 8

data security- important to the database

Answer 8

since all the data is in one place, we need A LOT OF DATA SECURITY!!!!

Question 9

data integrity- important to the database

Answer 9

data must meet certain constraints- there are no alphabetic characters in the sin fieldd

Question 10

data independance- importnt to the database

Answer 10

applications and data are independant of one another- that is, applications and data are not linked to each othe. so all applications are able to access the same data

Question 11

The Data Hierarchy

Answer 11

bits -> databases

Question 12

What is a bit

Answer 12

BINARY DIGIT, represents the smallest unit of data a computer can proccess

Question 13

Binary

Answer 13

means that a bit consist only of a 0 or 1

Question 14

What is a group of eight bits

Answer 14

byte

Question 15

Byte

Answer 15

-8 bits, represents asingle character

Question 16

Examples of a byte

Answer 16

a letter, a number, or a symbol

Question 17

what is a collection of bytes calles

Answer 17

a FIELD (that is a small group of words, word, or an ID number)

Question 18

What is a Field

Answer 18

describes an entity, can contain data other than text and numbers

(Collection of bytes)

Question 19

What is a logical grouping of related fields called

Answer 19

a record

Question 20

what is a recrod

Answer 20

collection of related fields

EX: the apple tunes store is the record, the songs are fields

Question 21

What is a logical grouping of related records called?

Answer 21

a data file or a TABLE

Question 22

WHAT is a data file/ table

Answer 22

related records

Question 23

what is a logical grouping of related files

Answer 23

database

Question 24

bit, byte, field, record, table, database

Answer 24

this is the order

Question 25

what is a database management system DBMs

Answer 25

set of programs that gives users the tools to create and maange a database

Question 26

what

Question 27

what does managing a database mean

Answer 27

process of adding delecting accessing modifying and analyzing data !!

Question 28

how can an org acccess the data in a database

Answer 28

using query and reporting tools that are part of the dbms

Question 29

example of a database architetctures

Answer 29

relational database model is popular and easy to use EX: microsoft accesss and oracle

Question 30

what is the relational database model

Answer 30

-Tables usually have rows and columns -the relational database contains tables!! and connects tables!

Question 31

why is the relational database model not one big table/ flat file

Answer 31

because this would involve too much data redundancy (different funcitonal areas needing the same info)

Question 32

how is data in the relational database organized

Answer 32

with the data model

Question 33

what is an entity

Answer 33

a person. place, a thing, or an event customer, employe, product, invoice, store

Question 34

which level of the data hierarchy is the entity?

Answer 34

records are usually entities

Question 35

what is an instance of an entity?

Answer 35

each row in an entity table! specific, unique representation of the entity this would be the numeric data NOT THE ATTRIBUTE!!

Question 36

what is each characterisitc of an entity called

Answer 36

the attribute!!! EX: Customer entity Age, address, name, preference

Question 37

What is a primary key, and why is it important?

Answer 37

every record (entity) in the database must contain at least one field that identifies that record (entity) UNIQUE IDENTIFIER!! THIS IS THE PRIMARY KEY

Question 38

what is a secondary key

Answer 38

another field that has some identify ingo about an entity, but does not identify the record completely!!! ex: instead of the students UCID, you use their major

Question 39

Foreign key

Answer 39

a field or sereral fields that like one table to another table@@

Question 40

what is big data

Answer 40

huge quantitis of data (diverse, high volume, high velocity) -unstructured EX: (EMAIL MESSAGES, VIDEOS, IMAGES, AUDIO FIELDS)

Question 41

strucutred data

Answer 41

highly organized in fixed field in a relational database

Question 42

4 categories of big data

Answer 42

1) traditional enterprise data 2) machine/sensor generated data 3) social data (blogs/feedback) 4)images captured by machines

Question 43

3 characteristics of big data

Answer 43

VOLUME: lots of data (tradiitonal=invoices, non traditional=clicks) VELOCITY: flowing at a high rate VARIETY: more and more TYPES OF DATA