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Chapter 11 Databases Chapter 11 © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Learning Objectives Distinguish between the physical and logical views of data Describe how data is organized: characters, fields, records, tables, Computing Essentals 2017 and databases Define key fields and how they are used to integrate data in a database Define and compare batch processing and real-time processing Describe databases, including the need for databases and database management systems (DBMS) Describe the five common database models: hierarchical, network, relational, multidimensional, and object-oriented Distinguish among individual, company, distributed, and commercial databases Describe strategic database uses and security concerns © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Introduction Like a library, secondary storage is designed to store information End users need to understand Computing Essentals 2017 How information is organized in fields, records, tables and databases The different types of databases and structures Competent end users need to be able to find information that is stored in databases © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Data Facts or observations about people, places, things, and events Used to be only numbers, letters, and symbols, but now also includes: Computing Essentals 2017 Audio, music, photographs, and video Two ways to view data Physical view focuses on the actual format and location of data Logical view focuses on the meaning, content, and context of the data © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Data Organization Logic view – data is organized into groups or categories Computing Essentals 2017 Character – single letter, number, or special character Field – group of related characters Record – collection of related fields Table – collection of related records Database – integrated collection of logically related tables Primary Key Unique identifier  Used to create relationships between tables © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Batch Processing Data is processed in two ways: batch and real-time Data is collected over a period of time and the processing Computing Essentals 2017 happens later all at one time © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Real-Time Processing Computing Essentals 2017 Also known as online processing because it happens immediately during the transaction © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Database Collection of integrated data Logically related files and records Databases address Computing Essentals 2017 data redundancy – same information in multiple files data integrity – accurate updating of files Advantages to having databases Sharing – between departments of an organization Security – limited access Less data redundancy – decrease unnecessary duplication Data integrity – reduce likelihood of inaccurate data © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Database Management Database Management System (DBMS) Software that enables users to create, modify, and gain access to data Software made up of: Computing Essentals 2017 DBMS engine – bridge between the logical view of data and the physical Data definition subsystem – defines the logical structure by using: Data dictionary or schema Contains a description of the structure of data © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part DBMS (Cont.) Data manipulation subsystem provides tools for maintaining and analyzing data Data Maintenance – maintaining data Analysis Tools used to view parts of the data Computing Essentals 2017  Query-by-example (QBE)  Structured query language (SQL) Application generation subsystem provides tools to create data entry Data administration subsystem helps manage the overall database Database Administrators (DBAs) administer the database Processing rights to determine who has access to the databases © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part DBMS Structure DBMS Programs are designed to work with data that is logically structured or arranged in a particular way Database model Computing Essentals 2017 Model defined rules and standards for data in a database © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Hierarchical Database Fields or records structured in nodes Nodes - points connected like branches of an upside-down tree Computing Essentals 2017 One parent per node Parent can have several child nodes One-to-many relationship Major concern is that if your parent node is deleted then so are all subordinate child nodes © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Computing Essentals 2017 Network Database Hierarchical node arrangement Each child node may have more than one parent node many-to-many relationship Additional connections between parent and child are Pointers Nodes can be reached through multiple paths © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Computing Essentals 2017 Relational Database A more flexible type where there are no access paths down a hierarchy Data stored in table called a relation Tables consist of rows and columns Tables related via a common data item / key field © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Multidimensional Database A variation and an extension of the relational model Includes a data cube Extension of the two dimensional data model to include Computing Essentals 2017 additional or multiple dimensions Good for representing complex relationships Advantages over relational databases Conceptualization provides users with an intuitive model in which complex data and relationships can be conceptualized Processing speed for analyzing and querying a large multidimensional database is faster © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Object-Oriented Database Computing Essentals 2017 Store data as well as instructions to manipulate data Organize data using Classes – general definitions Objects – specific instances of class containing data and instructions to manipulate the data Attributes – data fields an object possesses Methods – instructions for retrieving or manipulating attribute values © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Types of Databases Computing Essentals 2017 Individual or Persona Computer Database Integrated files used by just one person Company Common operational or commonly used files shared in an organization Distributed Database spread geographically and accessed using database server Commercial or Information Utilities or Data Banks Enormous database that organizations develop to cover particular subjects Examples Dialog Information Services Dow Jones Interactive Publishing Lexis Nexis © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Database Uses and Issues Strategic uses Data warehouse – storing in a database Computing Essentals 2017 for special use Data mining – used to search data warehouses Security Databases are valuable so protection necessary Protected by firewalls © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Careers In IT Database administrators Determine the most efficient Computing Essentals 2017 ways to organize and access a company’s data Responsible for database security and backing up the system Employers look for Bachelors degree in Computer Science or Information Systems Technical experience Database administrators can expect to earn $76,000 to $98,000 annually © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part A Look to the Future ~ The Future of Crime Databases Can criminal behavior be predicted ? Computing Essentals 2017 Research institutions have been looking into patterns that could predict criminal behavior If patterns could be found Just need to find individuals with these characteristics © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Open-Ended Questions (Page of 2) Computing Essentals 2017 Describe the five logical data groups or categories What is the difference between batch processing and realtime processing? Identify and define the five parts of DBMS programs © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part Open-Ended Questions (Page of 2) Computing Essentals 2017 Describe each of the five common database models What are some of the benefits and limitations of databases? Why is security a concern? © 2017 by McGraw-Hill Education This proprietary material solely for authorized instructor use Not authorized for sale or distribution in any manner This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part ... Distinguish between the physical and logical views of data Describe how data is organized: characters, fields, records, tables, Computing Essentals 2017 and databases Define key fields and how they are... a database Define and compare batch processing and real-time processing Describe databases, including the need for databases and database management systems (DBMS) Describe the five common database... Two ways to view data Physical view focuses on the actual format and location of data Logical view focuses on the meaning, content, and context of the data © 2017 by McGraw-Hill Education This

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