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Fundamentals of Information Systems, Seventh Edition
1Fundamentals of Information Systems,
Seventh Edition
Chapter 3Data Centers,
and Business Intelligence
Why Learn About Database Systems, Data
Centers, and Business Intelligence?
• Database:
– A database is an organized collection of data.
– Databases also help companies generate information to reduce costs, increase profits
• Database management system (DBMS):
– Group of programs that manipulate the database
– Provide an interface between the database and its users and other application programs
• Database administrator (DBA):
– Skilled IS professional who directs all activities related to an organization’s database
Fundamentals of Information Systems, seventh Edition
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The Hierarchy of DataBits, characters, fields, records, files,
and databases• Data is generally organized in a hierarchy that
begins with the smallest piece of data used by computers (a bit) and progresses through the hierarchy to a database.
• Bit (a binary digit):
– Circuit that is either on or off
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The Hierarchy of Data (continued)
• Byte:
– Typically made up of eight bits
– Each byte represents a character, which is the basic building block of most information.
• Character:
– Basic building block of information
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The Hierarchy of Data (continued)
• Field:
– Name, number, or combination of characters that describes an aspect of a business object or activity
• Record:
– Collection of related data fields
• File:
– Collection of related records
• Database:
– Collection of integrated and related filesFundamentals of Information Systems,
Seventh Edition5
Data Entities, Attributes, and Keys
• Entity:
• General class of people, places, or things (objects) for which data is collected, stored, and maintained.
• Examples of entities include employees, inventory, and customers.
• Attribute:
• Characteristic of an entity• For example, employee number, last name, first name, hire date, and
department number are attributes for an employee.
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• Key:
• Field or set of fields in a record that is used to identify the record
• Primary key:
• Field or set of fields that uniquely identifies the record
Data Entities, Attributes, and Keys (continued)
Fundamentals of Information Systems, Seventh Edition 8
The Database Approach
• The database approach:
– Traditional approach to data management:
• Each distinct operational system used data files dedicated to that system
– Database approach to data management:
• Pool of related data is shared by multiple application programs
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Traditional approach to data management
File-Based System ( traditional DB)
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Data Centers, Data Modeling and Database Characteristics
• When building a database, an organization must consider:
– Content: What data should be collected and at what cost?
– Access: What data should be provided to which users and when?
– Logical structure: How should data be arranged so that it makes sense to a given user?
– Physical organization: Where should data be physically located?
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Data Center
• Climate-controlled building or set of buildings that house database servers and the systems that deliver mission-critical information and services
• Traditional data centers:
– Consist of warehouses filled with row upon row of server racks and powerful cooling systems
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Data Center (continued)
• Many organizations now use large shipping containers packed with racks of servers and cooled to easily connect and set up
• Businesses and technology vendors working to develop green data centers that run more efficiently and require less energy for processing and cooling
• Backup and security procedures for data centers can be a concern
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Data Modeling
• Data model:
– Diagram of data entities and their relationships
• Enterprise data modeling:
– Starts by investigating the general data and information needs of the organization at the strategic level
• Entity-relationship (ER) diagrams:
– Data models that use basic graphical symbols to show the organization of and relationships between data Fundamentals of Information Systems,
Seventh Edition15
The Relational Database Model
• Relational model:
– Describes data using a standard tabular format
– Each row of a table represents a data entity (record)
– Columns of the table represent attributes (fields)
– The domain is the range of allowable values for data attributes
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The Relational Database Model (continued)
• Data cleanup
– Process of looking for and fixing inconsistencies to ensure that data is accurate and complete
– Database normalization is often used to clean up problems with data
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Normalization
• A database business process to break up data into the smallest possible parts.
• Break out all the repeating values in tables and save them into other related tables.
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Overview of Database Types
• Flat file
– Simple database program whose records have no relationship to one another
– Can called Text database
– Ex: Excel sheet
• Single user
– Only one person can use the database at a time
– Can called Desktop databse
– Examples: Access, FileMaker Pro, and InfoPath
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Database Types (Cont.)
• Multiple users ( R-DBMS)
– Allow dozens or hundreds of people to access the same database system at the same time
– Examples: Oracle, Microsoft, Sybase, and IBM
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Storing and Retrieving Data
• When an application program needs data it requests the data through the DBMS
• Concurrency control deals with the situation in which two or more users or applications need to access the same record at the same time
– It is applied to coordinate simultaneous transactions while preserving data integrity.
– It is about to control the multi-user access of database. Fundamentals of Information Systems,
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Database Management Systems
• Creating and implementing the right database system ensures that the database will support both business activities and goals
• Capabilities and types of database systems vary considerably
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Manipulating Data and Generating Reports
• Data Definition Language (DDL)
– Creating and defining database structure.
– Ex: CREATE, ALTER, DROP
• Data Manipulation Language (DML)
– Statements for managing data within database
– Ex: SELECT, INSERT, DELETE
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Manipulating Data and Generating Reports (continued)
• Structured Query Language (SQL):
– Adopted by the American National Standards Institute (ANSI) as the standard query language for relational databases
• Once a database has been set up and loaded with data, it can produce reports, documents, and other outputs
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User Views
• External schema
– To view all contents of database
• Sub-schema
– To view part of DB
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Database Administration
• DBA (Physical Design) :
– Works with users to decide the content of the database
– Works with programmers as they build applications to ensure that their programs comply with database management system standards and conventions
• Data Administrator (DA – Logical Design):
– Responsible for defining and implementing consistent principles for a variety of data issues
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Popular Database Management Systems
• Popular DBMSs for end users:
– Microsoft’s Access and FileMaker Pro
– Number of open source DBMS including PostgreSQL, MySQL, and CouchDB
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Database Virtualization
• Uses virtual servers and operating systems to allow two or more database systems, including servers and DBMSs to act like a single, unified database system
• Allows more efficient use of computing resources, reduce costs, and provide better access to critical information
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Using Databases with Other Software
• DBMSs can act as front-end or back-end applications:
– Front-end applications interact directly with people
– Back-end applications interact with other programs or applications
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Linking the Company Database to the Internet
• Security always a concern when linking a database to the Internet
• Semantic Web:
– Developing a seamless integration of traditional databases with the Internet
– Provides metadata with all Web content using technology called the Resource Description Framework (RDF)
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Data Warehouses, Data Marts, and Data Mining
• Data warehouse
– Database that holds business information from many sources in the enterprise
• Data mart
– Subset of a data warehouse
• Data mining
– Information-analysis tool that involves the automated discovery of patterns and relationships in a data warehouse
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Distributed Databases
• Distributed database:
– Database in which the data may be spread across several smaller databases connected via telecommunications devices
– Gives corporations more flexibility in how databases are organized and used
• Replicated database:
– Holds a duplicate set of frequently used data.
– Can be as whole DB (Like backup) or Sub set.
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Distributed Databases (cont.)
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Figure to illustrate the idea of distributed DB
Figure to show the DB replication
Business Intelligence
• Involves gathering enough of the right information:
– In a timely manner and usable form and analyzing it to have a positive impact on business strategy, tactics, or operations
• Competitive intelligence:
– Limited to information about competitors and the ways that knowledge affects strategy, tactics, and operations
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Business Intelligence (continued)
• Counterintelligence:
– Steps organization takes to protect information sought by “hostile” intelligence gatherers
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Summary
• Traditional file-oriented applications are often characterized by program-data dependence
• The relational model places data in two-dimensional tables
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Summary (continued)
• A DBMS is a group of programs used as an interface between a database and its users and other application programs
• DBMS basic functions include:
– Providing user views
– Creating and modifying the database
– Storing and retrieving data
– Manipulating data and generating reports
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Summary (continued)
• Database virtualization allows organizations to use computing resources more efficiently, reduce costs, and provide better data access
• Database administrator plans, designs, operates, secures, monitors, and maintains databases
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Summary (continued)
• Data warehouses are relational database management systems specifically designed to support management decision making
• Data mining allows the automated discovery of patterns and relationships in a data warehouse
• Predictive analysis combines historical data with assumptions about future conditions to forecast future events
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Summary (continued)
• Business intelligence is the process of getting enough of the right information in a timely manner and usable form
• Competitive intelligence involves information about competitors and their strategy, tactics, and operations
• Counterintelligence is the steps an organization takes to protect information from hostile intelligence gathers
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