CH06.1

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Week 7.1
ISA 235
Dr. Zelalem Bachore
1
SECTION 6.1
DATA,
INFORMATION, AND
DATABASES
2
CHAPTER OVERVIEW

SECTION 6.1 – Data, Information, Databases
 The Business Benefits of High-Quality Information
 Storing Information Using a Relational Database
Management System
 Using a Relational Database for Business Advantages
 Driving Websites with Data

SECTION 6.2 – Business Intelligence
 Data Warehousing
 Business Intelligence
 The Power of Big Data
 Data Mining
 Data Analytics
3
Four primary traits that help determine
the value of information
4
Information Type:
Transactional and Analytical
•
Transactional information – Encompasses all of the
information contained within a single business process or
unit of work, and its primary purpose is to support the
performing of daily operational tasks
•
•
Withdrawing cash from an ATM, making an airline
reservation, purchasing stocks..
Analytical information – Encompasses all organizational
information, and its primary purpose is to support the
performing of managerial analysis tasks
•
Includes external organizational information such as market,
industry and economic conditions
•
Trends, sales, product statistics, and future growth
projections
•
Cost/benefit analysis, sales forecast, market trends,
industry trends, and regulations
5
Information Type:
Transactional and Analytical
Storms and Pop-Tarts?
Building a new plant, hiring or reducing
workforces, introducing a new product
6
etc.
Four primary traits that help determine
the value of information
7
Information Timeliness

Timeliness is an aspect of information that
depends on the situation
In some firms or industries, information that is a
few days or weeks old can be relevant, while in
others information that is a few minutes old can
be almost worthless.
911
response
centers,
stock traders, and banks,
require up-to-the-second
information
Other organizations, such as
insurance and construction
companies,
require
only
daily
or
even
weekly
information.
8
Four primary traits that help determine
the value of information
9
Information Quality

Business decisions are only as good as the
quality of the information used to make
the decisions

You never want to find yourself using
technology to help you make a bad
decision faster
10
Information Quality

Five Characteristics of High-quality Information
Accuracy Are all the values correct?
For example, is the name spelled
correctly? Is the dollar amount
recorded properly?
Completeness Are any of the values
missing? For example, is the address
complete including street, city, state,
and zip code?
Consistency
Is
aggregate
or
summary information in agreement
with detailed information?
For example, do all total fields
equal the true total of the
individual fields
Uniqueness Is each transaction,
entity, and event represented only
once in the information?
For example, are there any
duplicate customers?
Timeliness Is the information current
with respect to the business
requirements? For example, is
11
information updated
weekly, daily, or
hourly?
Without a first name it would be impossible to correlate this
customer with customers in other databases (Sales, Marketing,
Billing, Customer Service) to gain a compete customer view
(CRM)
12
Without a complete street address there is no possible way to
communicate with this customer via mail or deliveries.
13
If this is the same customer with duplicate data, the company will
waste money sending out two sets of promotions and advertisements
to the same customers. It might also send two identical orders and
have to incur the expense of one order being returned
14
This is a good example of where cleaning data is difficult because this
may or may not be an error. There are many times when a phone and
a fax have the same number. Since the phone number is also in the email address field, chances are that the number is inaccurate
15
The business would have no way of communicating with
this customer via e-mail
16
The company could determine the area code based on the
customer’s address. This takes time, which costs the company
money. This is a good reason to ensure that information is
entered correctly the first time.
17
The four primary sources of low quality
information include:

Customers intentionally enter inaccurate
information to protect their privacy

Different entry standards and formats
MM/DD/YYYY -> DD/MM/YYYY

Operators enter abbreviated or erroneous
information by accident or to save time

Third party and external information contains
inconsistencies, inaccuracies, and errors
18
Understanding the Costs of
Using Low-Quality Information

Potential business effects resulting from
low quality information include
 Inability
to accurately track customers
 Difficulty identifying valuable customers
 Inability to identify selling opportunities
 Marketing to nonexistent customers
 Difficulty tracking revenue
 Inability to build strong customer
relationships
19
Understanding the Benefits of
Good Information

High quality information can
significantly improve the chances
of making a good decision

Good decisions can directly impact
an organization's bottom line
20
STORING INFORMATION IN A
RELATIONAL DATABASE

Information is everywhere in an organization

Every business decision is based on information

Information is stored in databases
 Database
– maintains information about various types
of objects (inventory), events (transactions), people
(employees), and places (warehouses)
21
STORING INFORMATION IN A
RELATIONAL DATABASE

Database management systems (DBMS) –Allows
users to create, read, update, and delete data in a
relational database
22
Database Building Blocks:

Entity

Attributes

Data points

Data Model

Primary/Foreign Keys

Data Dictionary
23
Entities
 An
entity is an object or event, real or
abstract, about which we would like to store
data.
 Identifying
Entity Types

What information is required by the business?

What kind of business decision is required?

Things that are of interest to the business that
need to be remembered in order to manage and
track them.
 Miami
University: Students, Faculty, Departments,
Courses, Suppliers, Administrators etc.
 All
Entities will end up as Tables in your database!
24
Finding Entity Types
Interviews
Business
with users
forms
Reports
Operation
manuals
25
Database Building Blocks:

Entity

Attributes

Data points

Data Model

Primary/Foreign Keys

Data Dictionary
26
Attributes

Attribute are characteristics that can be
used to describe specific Entity Instances

Entities will be used to store attributes
 Customer
Entity: Nine Attributes
27
Database Building Blocks:

Entity

Attributes

Data points

Data Model

Primary/Foreign Keys

Data Dictionary
28
Data Point/Data
Element/Data Field
Data point: The smallest or basic unit of information.
Customer ID
Customer
First Name
Customer
Last Name
Address
City
State
Zip
Phone
1771
Larry
Shimk
143 S.
Denver
NY
178908
911
1771
Caroline
Shimk
143 N. West
St.
Buffalo
NY
14321
716-333-4567
29
Database Building Blocks:

Entity

Attributes

Data points

Data Model

Primary/Foreign Keys

Data Dictionary
30
Primary & Foreign Keys

A Primary key is a key that uniquely identifies a row in
each table.
Customernum uniquely identifies the Customer table
and is the primary key of this table.
Every table should have a primary key!!
31
Primary & Foreign Keys

A Foreign key is a key borrowed from another related
table (that’s why its foreign) in order to make the
relationship between two tables.
Used to create a relationship! Logical Pointer

Think of it as a logical pointer!!

32

Which vendor supplies item “Claw Hammer”?

Need to connect the Vendor & Product tables to find the answer!! –> Foreign Key

Plug Vend_Code (PK, Vendor) into Product as a Foreign Key:

1) Used to create a r/s b/n entities
33

2) Used as a PK elsewhere (makes it foreign)
Do we really need Foreign Keys?
232
Annelise Crystal
608
224-2134
Claw Hammer
232
Annelise Crystal
608
224-2134
Jack Hammer

Which vendor supplies item “Claw Hammer”?
34
Database Building Blocks:

Entity

Attributes

Data points

Data Model

Primary/Foreign Keys

Data Dictionary
35
Data Model:
Data model: Logical data structures that detail the
relationships among data elements using graphics or
pictures.
Data model: Relationship b/n Agent & Customer
•
An Agent will work with multiple (Infinity) Customers
•
Many Customers will work with a single Agent
36
The Importance of Data Models

Data model
 Relatively
simple representation, usually
graphical, of complex real-world data
structures
 Communications
tool to facilitate
interaction among the designer, the
applications programmer, and the end
user

1st
Good database design uses an appropriate
data model as its foundation!
37
SQL Assignment: Using data model WWImporters ERD.PNG
Database Building Blocks:

Entity

Attributes

Data points

Data Model

Primary/Foreign Keys

Data Dictionary
38
STORING INFORMATION IN
A RELATIONAL DATABASE

Metadata – Data about data


Image: Size, Resolution, Date of creation etc..
Data dictionary – Compiles all of the metadata about the
data elements in the data model

DBMS will create a data dictionary as you start working on your
objects!
• A data dictionary includes the names and
descriptions of the objects and the fields contained
in each table. It also documents information about
the data type, field length and other things such as
validation.
• Read Only!
39
1st SQL Assignment: Using data dictionary WWImporters Schema Detail.pdf
USING A RELATIONAL DATABASE FOR BUSINESS
ADVANTAGES
Handle changes quickly and easily
Provide users with different views
Have only one physical view
Physical storage of information on
a storage device
Have multiple logical views
Involves how information appears
to users and how it can be
organized and retrieved
40
USING A RELATIONAL DATABASE FOR
BUSINESS ADVANTAGES
Information integrity – measures the quality of information
Integrity constraint – rules that help ensure the quality of
information
1) Relational integrity constraint
2) Business-critical integrity constraint
41
1) Relational Integrity Constraint
Rules that enforce basic and fundamental information-based
constraints.
3464
10/8/2018
45
NY9001
$15.00
$145.00
Would not allow someone to create an order for a nonexistent
customer
42
2) Business-Critical Integrity Constraint
Enforce business rules vital to an organization’s success and
often
A business rule defines how a company performs
certain aspects of its business and typically results in
either a yes/no or true/false answer.
E.g. Merchandise returns are allowed within 10
days of purchase
Require more insight and knowledge into the business than
relational integrity constraints
43
What is a database-driven Web site?
1.
Static Web pages
 Data
is stored in .html files
 Won't
2.
change until someone changes their source codes
Dynamic Web pages – Database driven website
 Data
is stored in a database
 Content
providers update their data through CMS
(Content Management System), Administrative area
 When
the "Submit" button is clicked, their
details/content is inserted into the database.
 Others
can view the content after refreshing their
page.
 Most
discussion and blogs forums, Amazon, CNN
When do we need a
database-driven web site?
We would need a database-driven Web site if
our information changes very often, just like
in a banking site
 Most organizations have a great deal of
information in databases and could benefit if
this information is made available online

 When
the content on a site reaches critical mass,
it's time to stop managing it as “resources
embedded in static HTML" and start to create a
database-driven Web site
Why do we need databasedriven Web sites?


Web pages of database-driven Web sites are created
dynamically (in real time) thus giving a Web site visitor
an up-to-date view of information stored in the
database.
Users can do their own maintenance via a set of Webbased data entry forms
 Such


as we can change our address, credit card
information of our Amazon account by ourselves
The information that the Web site visitor sees on a
dynamic Web page can be quickly customized
 For example, the sort order of the items can be
changed or certain database fields can be shown or
hidden
It is easy for Web masters to maintain the Web sites
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