Databases and Managing Information

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Chapter 6
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Problems of managing Data Resources in a
Traditional File Environment
Effective IS provides user with Accurate,
timely and relevant information
Many businesses do not have this kind of
information
A computer system organizes data in a
hierarchy that starts with bits and bytes and
progresses to fields, records, files, and
databases.
Traditional File Environment- some terms:
 Bit- smallest
 Byte- 8 bits multiple
 Field- column
 Record- row
 Entity- objective, organization
 Attribute- characteristics, age
 File- table
 Database- multiple files related- RDBMS
Management Information Systems
Chapter 6 Foundations of Business Intelligence: Databases
and Information Management
The Data Hierarchy
A computer system
organizes data in a
hierarchy that starts
with the bit, which
represents either a 0
or a 1. Bits can be
grouped to form a
byte to represent one
character, number, or
symbol. Bytes can be
grouped to form a
field, and related
fields can be
grouped to form a
record. Related
records can be
collected to form a
file, and related files
can be organized
into a database.
Figure 6-1
Organizing Data in a Traditional File Environment
The use of a traditional approach to file processing encourages each functional area in a corporation to
develop specialized applications and files. Each application requires a unique data file that is likely to be a
subset of the master file. These subsets of the master file lead to data redundancy and inconsistency,
processing inflexibility, and wasted storage resources.
Figure 6-2
Organization has different departments. Each
developed their own systems and files
 Data redundancy and inconsistency:
It is the presence of duplicate data in multiple data files
so that the same data are stopped in more than place
or location. Data redundancy occurs when different
groups in an organization independently collect the
same piece of data and store it independently of each
other.
 Program data dependence:
It is the coupling of data stored in files and the specific
programs required to update and maintain those files
such that changes in programs required to update
and maintain those files such that changes in
programs require changes to the data
Lack of flexibility:
A traditional file system can deliver routine
scheduled reports after existence
programming efforts
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Poor security:
• Lack of control, widespread
• Who is accessing and making changes
Lack of Data sharing and
Availability
• Information cannot be related
• Impossible to share or access in a
timely manner.
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Collection of data organized to serve many applications
efficiently by centralizing the data and controlling the
redundant data.
Database management system:
Is software that permits an organization to centralize data, manage them efficiently
and provides access to the stored data by application programs.
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Interfaces between application programs and physical data files
Separates logical and physical views of data
Solves problems of traditional file environment
Controls redundancy by minimizing isolated files in which same data
is repeated.
• Eliminated inconsistency
• Enables central management and security
DATA DEFINITION CAPABILITY, DATA
DICTIONARY CAPABILITY AND DATA
MANPULATION LANGUAGE (SQL)
 Software that permits an organization to
centralize data, manages them efficiently,
and provides access to the stored data by
application programs.
 Separates the Logical and physical view of the
data
The Database Approach to Data Management
Human Resources Database with Multiple Views
A single human resources database provides many different views of data, depending on the information
requirements of the user. Illustrated here are two possible views, one of interest to a benefits specialist and
one of interest to a member of the company’s payroll department.
Figure 6-3
Relational DBMS
 Most popular type of DBMS
 Represents data into two dimensional tables
called relations
 Concept of primary and foreign key
 RDBMS have three basic operations: SELECT,
JOIN, PROJECT
 QUERYING AND REPORTING
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The Database Approach to Data Management
Relational Database Tables
A relational
database organizes data in the form of two-dimensional tables.
Illustrated here are tables for the entities SUPPLIER and PART showing how
they represent each entity and its attributes. Supplier_Number is a primary key
for the SUPPLIER table and a foreign key for the PART table.
Figure 6-4A
The Database Approach to Data Management
Relational Database Tables (cont.)
Figure 6-4B
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Databases that can store drawings, images,
videos, photographs and voices along with
the structured numbers and characters.
Relatively slow than RDBMS
HYBRID OODBMS- it has the capabilities of
RDBMS and OODBMS
PRINCIPAL TOOLS AND TECHNOLOGIES FOR
ACCESSING INFORMATION FROM DATABASE TO
IMPROVE BUSINESS PERFORMANCE AND DECISION
MAKING
 Businesses use their databases to keep track of
basic transactions such as paying employees and
suppliers, processing orders, keeping track of
customers etc;
 In large databases from separate functions large
amount of data is stored and there are special
capabilities and tools for analyzing large amount
of data and for accessing this data
These capabilities include:
 Data warehousing
 Data mining
 Tools for accessing internal databases
through the web
DBMS includes tools for accessing and
manipulating information in databases. Most
DBMS have a specialized language called a
data manipulation language, that is used to
add, change, delete, and retrieve the data in
the database.
Database design also considers how the data
are to be distributed. Information systems
can be designed with a centralized database
that is used by a single central processor or
by multiple processors in a client/ server
network.
The Database Approach to Data Management
Distributed Databases
There are alternative ways of distributing a database. The central database can be partitioned (a) so that each remote
processor has the necessary data to serve its own local needs. The central database also can be replicated (b) at all
remote locations.
Figure 6-12
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Businesses use their databases to keep track
of basic transactions, such as paying
suppliers, processing orders, keeping track of
customers and paying employees.
If data is required from:
 Different departments
 Should be complete
 Updated
 Past Data
Then data warehousing solves your problems
DATA WAREHOUSE CONSOLIDATES AND
STANDARDIZES INFORMATION FROM
DIFFERENT OPERATIONAL DATABASES SO
THAT THE INFORMATION CAN BE USED
ACROSS THE ENTERPRISE FOR MANAGEMENT
ANALYSIS AND DECISION MAKING
Data can be accessed but cannot be altered
Using Databases to Improve Business Performance and
Decision Making
Components of a Data Warehouse
The data warehouse extracts current and historical data from multiple
operational systems inside the organization. These data are combined
with data from external sources and reorganized into a central database
designed for management reporting and analysis. The information
directory provides users with information about the data available in
the warehouse.
Figure 6-13
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Data marts focuses on single subject area
online of business
Decentralized Subsets of data warehouses
which is highly focused or summarized. It is
placed in separate database for a specific
population of the users
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Once data has been captured and organized
it is available for further analysis
Several tools are available for analyzing data
to see new patterns, relationships and
insights.
The tools for consolidating analyzing and
providing access to vast amount of data to
help users make better decisions are often
referred as “Business Intelligence (BI)”
Using Databases to Improve Business Performance and
Decision Making
Business Intelligence
A series of analytical tools
works with data stored in
databases to find patterns
and insights for helping
managers and employees
make better decisions to
improve organizational
performance.
Figure 6-14
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Software for querying and reporting
Tools for multidimensional data analysis
(Online analytical processing OLAP)
Data mining
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Lets assume you sell four products in three
different regions of the country?
If you want an answer for a simple question
like “how many of the Product A was sold in
the last quarter?”. Simple query would answer
the question but lets say the question is “how
many of product A was sold in each of your
sales region and compare the actual and
projected sales?”
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For that you will need OLAP which will enable
user to se same data in different ways
Using Databases to Improve Business Performance and
Decision Making
Multidimensional Data Model
The view that is showing is
product versus region. If
you rotate the cube 90
degrees, the face that will
show is product versus
actual and projected sales.
If you rotate the cube 90
degrees again, you will see
region versus actual and
projected sales. Other views
are possible.
Figure 6-15
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Data mining is the process of extracting patterns
from data. Data mining is becoming an
increasingly important tool to transform this data
into information.
It is commonly used in a wide range of profiling
practices, such as marketing, surveillance, fraud
detection and scientific discovery
Data mining can be used to uncover patterns in
data but is often carried out only on samples of
data
The mining process will be ineffective if the
samples are not a good representation of the
larger body of data
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Data mining cannot discover patterns that
may be present in the larger body of data if
those patterns are not present in the sample
being “mined”. Inability to find patterns may
become a cause for some disputes between
customers and service providers. Therefore,
data mining is not foolproof, but may be
useful if sufficiently representative data
samples are collected
Database and the Web
 If you have used web to order something
online then you are using a website which is
linked to a database
 There are number of advantages in using the
web to access an organization internal
databases
WEB BROWSER SOFTWARE IS MUCH EASIER TO
HANDLE
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Establishing an Information Policy:
An information policy specifies the
organization’s rules for sharing,
dissemination, acquiring, standardizing,
classifying and inventorying information.
Information policy lays out specific
procedures and accountabilities, identifying
which users and organizational units can
share information, where information can be
distributed and who is responsible or
updating and maintaining the information.
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A well-designed database and information
policy will go a long way towards ensuring
that the business has the information it
needs. However, additional steps must be
taken to ensure that the data in
organizational databases are accurate and
remain reliable.
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