Chapter 5 In Class Notes

Question 1

Q1: What Is the Purpose of a Database?

Answer 1

• Organize and keep track of things
• Keep track of multiple themes
• General rule:
– Single theme store in a spreadsheet
– Multiple themes require a database

Question 2

Q2: What Is a Database?

Answer 2

A self-describing collection of integrated
records
– Bytes are grouped into columns (a.k.a. fields)
– Columns are grouped into rows (a.k.a. records)

Question 3

Rows in a database are also called

Answer 3

Records

Question 4

Columns in a database are also called

Answer 4

fields

Question 5

Characters in a database are also called

Answer 5

bytes

Question 6

Bytes are grouped into

Answer 6

columns

Question 7

Columns are grouped into

Answer 7

rows

Question 8

Components of a Database. 3 things

Answer 8

Tables or Files + relationships among rows in tables + metadata = database

Question 9

What Are Relationships Among Rows?

Answer 9

For example a student can be in the email table and also the student table. There’s a relationship among rows.

Question 10

Key:

Answer 10

A
column or
group of
columns that
identifies a
unique row in
a table

Question 11

Databases that carry their data in the form of tables
and that represent relationships using foreign keys
are called

Answer 11

relational databases

Question 12

Metadata:

Answer 12

data that describes data

Question 13

Q3: What Are the Components of a

Database Application System? 4 of them

Answer 13

1. User
2. Database Application
3. Database management system
4. Tables, Relationships, Metadata

Question 14

Database Management System

Answer 14

A software program used to create, process, and administer a database

Question 15

Database =

Answer 15

a collection of tables, relationships and metadata

Question 16

The DBMS

• Three Functions

Answer 16

– Create tables, relationships, and other structures in the
database
– Process the database (using SQL or another processing
language)
• Read
• Insert
• Modify
• Delete data
– Provide tools to assist in the administration of the
database (e.g. security and optimization)

Question 17

What are the 4 processes of a database

Answer 17

Read
Insert
Modify
Delete Data

Question 18

Structured Query Language (SQL)

Answer 18

– International standard

– Used by most popular DBMS

Question 19

Q4: How Do Database Applications

Make Databases More Useful?

Answer 19

A collection of forms, reports,
queries, and application programs that process a database.
• Provide process logic specific for a business need
• Enable processing via Internet

Question 20

Q5: How Are Data Models Used for

Database Development? What is the process. 4 things

Answer 20

1. You have the forms reports and queries with all the requirements.
2. You then create a data model with entities and relationships
3. Then you create database design with tables that have foreign keys
4. Then you create the database

Question 21

What Is the Entity-Relationship (E-R)

Data Model?

Answer 21

• Tool for constructing data models
• Describes contents of a data model by defining entities and
relationships among entities
• Unified Modeling Language (UML), less popular, tool for
data modeling

Question 22

Q6: How Is a Data Model Transformed

into a Database Design?

Answer 22

1. Construct Adviser table and Student tables with key
   fields
2. Represent relationships by adding foreign keys
3. Create new table for N:M relationships

Question 23

Q7: What Is the Users’ Role in the

Development of Databases?

Answer 23

• Define what data database must contain
• Review data models for accuracy
• Final approval of data models

Question 24

Q8: 2022?

Answer 24

• Relational databases will look much different
• Use of non-relational data stores, called NoSQL will
be more common
• Major DBMS vendors lose out to open-source
products and shift focus to services supporting open
source software like Bigtable, Dynamo, Cassandra?
• Database models will be very different

Question 25

Popular DBMS products are?

Answer 25

DB2 from IBM. Access and SQL Server from Microsoft, and Oracle Database from the Oracle Corporation.

Question 26

Give an example of a lost update problem.

Answer 26

When two people are shopping online and they both are buying the same thing at the same time. They both order it, but they only had one.

Question 27

Enterprise DBMS

Answer 27

products process large organizational and workgroup databases.

Question 28

Personal DBMS

Answer 28

products are designed for smaller, simpler database applications.

Question 29

Logical representation of database data is called?

Answer 29

data model

Question 30

entity

Answer 30

some thing that the users want to track. Examples are Order, customer, salesperson, and item.

Question 31

describe characteristics of the entity. Examples are OrderNumber, OrderDate, SubTotal, Tax, Total

Answer 31

attributes

Question 32

Identifier

Answer 32

attribute or group of attributes whose value is associated with one and only one entity instance

Question 33

When you have a department entity and an advisor entity with a line going from the department to the advisor, what does it mean if the part of line touching the adviser is forked?

Answer 33

it's a crow's feet. Shows that a department may have more than one adviser.

Question 34

Suppose for Adviser's and Student's the relationship line was forked on both sides. What would this mean?

Answer 34

Mean's that an adviser can be related to many students and that a student can be related to many advisers

Question 35

.Relationships like the ones on the previous question are called.

Answer 35

many-to-many relationships.

Question 36

the process of converting a poorly structured table into two or more well-structured tables.

Answer 36

Normalization.

Question 37

Data integrity problem example?

Answer 37

Some rows indicate that the name of department 100 is Accounting and Finance and some indicate that the department 100 is accounting

Question 38

What does N:M look like?

Answer 38

crows feet on both sides

Question 39

What does 1:N look like

Answer 39

Crows feet on one side

Question 40

What does 1:1 say

Answer 40

one to one

Question 41

What does 1:N say

Answer 41

One to Many

Question 42

what does N:M say

Answer 42

Many to Many

Question 43

Maximum Cardinality

Answer 43

The maximum number of | entities that can be involved in a relationship

Question 44

Minimum Cardinality

Answer 44

The minimum requirements