Fundamentals of Information Systems, Seventh Edition

Transcription

1 Chapter 3 Data Centers, and Business Intelligence 1

2 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 2

3 The Hierarchy of Data Bits, 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 3

4 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 4

5 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 files 5

6 6 Fundamentals of Information Systems,

7 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. 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 Fundamentals of Information Systems, 7

8 Data Entities, Attributes, and Keys (continued) Fundamentals of Information Systems, 8

9 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 9

10 Traditional approach to data management File-Based System ( traditional DB) 10

11 The Database Approach (continued) 11

12 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? 12

13 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 13

14 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 14

15 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 15

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17 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 17

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19 The Relational Database Model Data cleanup (continued) 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 19

20 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. 20

21 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 21

22 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 22

23 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. 23

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25 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 25

26 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 26

27 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 27

28 User Views External schema To view all contents of database Sub-schema To view part of DB 28

29 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 29

30 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 30

31 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 31

32 Database Virtualization (Cont.) 32

33 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 33

34 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) 34

35 Data Warehouses, Data Marts, Data warehouse and Data Mining 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 35

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37 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. 37

38 Distributed Databases (cont.) Figure to show the DB replication Figure to illustrate the idea of distributed DB 38

39 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 39

40 Business Intelligence (continued) Counterintelligence: Steps organization takes to protect information sought by hostile intelligence gatherers 40

41 Summary Traditional file-oriented applications are often characterized by program-data dependence The relational model places data in twodimensional tables 41

42 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 42

43 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 43

44 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 44

45 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 45