© 2009 Pearson Education, Inc. Publishing as Prentice Hall 1 Chapter 10: The Internet Database Environment Modern Database Management 9 th Edition Jeffrey A. Hoffer, Mary B. Prescott, Heikki Topi

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 2 Objectives Definition of terms Definition of terms Explain the importance of attaching a database to a Web page Explain the importance of attaching a database to a Web page Describe necessary environment for Internet and Intranet database connectivity Describe necessary environment for Internet and Intranet database connectivity Use Internet terminology appropriately Use Internet terminology appropriately Explain the purpose of WWW Consortium Explain the purpose of WWW Consortium Explain purpose of XML for standardized data interpretation Explain purpose of XML for standardized data interpretation Explain XPath and XQuery Explain XPath and XQuery Explain the purpose of server-side extensions Explain the purpose of server-side extensions Describe Web services Describe Web services Compare Web server interfaces (CGI, API, Java servlets) Compare Web server interfaces (CGI, API, Java servlets) Describe Web load balancing methods Describe Web load balancing methods Explain plug-ins Explain plug-ins

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 3 Web Characteristics that Support Web-Based Database Applications Web browsers are simple to use Web browsers are simple to use Information transfer can take place across different platforms Information transfer can take place across different platforms Development time and cost have been reduced Development time and cost have been reduced Sites can be static (no database) or dynamic/interactive (with database) Sites can be static (no database) or dynamic/interactive (with database) Potential e-business advantages (improved customer service, faster market time, better supply chain management) Potential e-business advantages (improved customer service, faster market time, better supply chain management)

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 4 Figure 10-1 Database-enabled intranet/internet environment

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 5 Internet and Intranet Services Web server Web server Database-enabled services Database-enabled services Directory, security, authentication Directory, security, authentication File Transfer Protocol (FTP) File Transfer Protocol (FTP) Firewalls and proxy servers Firewalls and proxy servers News or discussion groups News or discussion groups Document search Document search Load balancing and caching Load balancing and caching

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 6 World Wide Web Consortium (W3C) An international consortium of companies working to develop open standards that foster the development of Web conventions so that Web documents can be consistently displayed on all platforms An international consortium of companies working to develop open standards that foster the development of Web conventions so that Web documents can be consistently displayed on all platforms See See

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 7 Web-Related Terms World Wide Web (WWW) World Wide Web (WWW) The total set of interlinked hypertext documents residing on Web servers worldwide The total set of interlinked hypertext documents residing on Web servers worldwide Browser Browser Software that displays HTML documents and allows users to access files and software related to HTML documents Software that displays HTML documents and allows users to access files and software related to HTML documents Web Server Web Server Software that responds to requests from browsers and transmits HTML documents to browsers Software that responds to requests from browsers and transmits HTML documents to browsers Web pages–HTML documents Web pages–HTML documents Static Web pages–content established at development time Static Web pages–content established at development time Dynamic Web pages–content dynamically generated, usually by obtaining data from database Dynamic Web pages–content dynamically generated, usually by obtaining data from database

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 8 Communications Technology IP Address IP Address Four numbers that identify a node on the Internet Four numbers that identify a node on the Internet e.g e.g Hypertext Transfer Protocol (HTTP) Hypertext Transfer Protocol (HTTP) Communication protocol used to transfer pages from Web server to browser Communication protocol used to transfer pages from Web server to browser HTTPS is a more secure version HTTPS is a more secure version Uniform Resource Locator (URL) Uniform Resource Locator (URL) Mnemonic Web address corresponding with IP address Mnemonic Web address corresponding with IP address Also includes folder location and html file name Also includes folder location and html file name Typical URL

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 9 Internet-Related Languages Hypertext Markup Language (HTML) Hypertext Markup Language (HTML) Markup language specifically for Web pages Markup language specifically for Web pages Standard Generalized Markup Language (SGML) Standard Generalized Markup Language (SGML) Markup language standard Markup language standard Extensible Markup Language (XML) Extensible Markup Language (XML) Markup language allowing customized tags Markup language allowing customized tags XHTML XHTML XML-compliant extension of HTML XML-compliant extension of HTML Java Java Object-oriented programming language for applets Object-oriented programming language for applets JavaScript/VBScript JavaScript/VBScript Scripting languages that enable interactivity in HTML documents Scripting languages that enable interactivity in HTML documents Cascading Style Sheets (CSS) Cascading Style Sheets (CSS) Control appearance of Web elements in an HML document Control appearance of Web elements in an HML document XSL and XSLT XSL and XSLT XMS style sheet and transformation to HTML XMS style sheet and transformation to HTML Standards and Web conventions established by World Wide Web Consortium (W3C)

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 10 XML Overview Becoming the standard for E-Commerce data exchange Becoming the standard for E-Commerce data exchange A markup language (like HTML) A markup language (like HTML) Uses elements, tags, attributes Uses elements, tags, attributes Includes document type declarations (DTDs), XML schemas, comments, and entity references Includes document type declarations (DTDs), XML schemas, comments, and entity references XML Schema (XSD) replacing DTDs XML Schema (XSD) replacing DTDs Relax NG–ISO standard XML database definition Relax NG–ISO standard XML database definition Document Structure Description (DSD)– expressive, easy to use XML database definition Document Structure Description (DSD)– expressive, easy to use XML database definition

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 11 XML Overview (cont.) Xpath Xpath One of a set of XML technologies supporting XQuery development, locating data in XML documents One of a set of XML technologies supporting XQuery development, locating data in XML documents XLink XLink XML markup language for creating hypertext links XML markup language for creating hypertext links XPointer XPointer Used along with Xlink for establishing hypertext links to URI references Used along with Xlink for establishing hypertext links to URI references XQuery XQuery XML transformation language allowing applications to query relational databases and XML data XML transformation language allowing applications to query relational databases and XML data

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 12 Sample XML Schema Schema is a record definition, analogous to the Create SQL statement, and therefore provides metadata

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 13 Sample XML Document Data XML data involves elements and attributes defined in the schema, and is analogous to inserting a record into a database

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 14 Another Sample XML Document

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 15 Sample XPath Expressions for PVFC.xml

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 16 Server-Side Extensions Programs that interact directly with Web servers to handle requests Programs that interact directly with Web servers to handle requests e.g. database-request handling middleware e.g. database-request handling middleware Figure 10-2 Web-to-database middleware

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 17 Web Server Interfaces Common Gateway Interface (CGI) Common Gateway Interface (CGI) Specify transfer of information between Web server and CGI program Specify transfer of information between Web server and CGI program Performance not very good Performance not very good Security risks Security risks Application Program Interface (API) Application Program Interface (API) More efficient than CGI More efficient than CGI Shared as dynamic link libraries (DLLs) Shared as dynamic link libraries (DLLs) Java Servlets Java Servlets Like applets, but stored at server Like applets, but stored at server Cross-platform compatible Cross-platform compatible More efficient than CGI More efficient than CGI

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 18 Web Servers Provide HTTP service Provide HTTP service Passing plain text via TCP connection Passing plain text via TCP connection Serve many clients at once Serve many clients at once Therefore, multithreaded and multiprocessed Therefore, multithreaded and multiprocessed Load balancing approaches: Load balancing approaches: Domain Name Server (DNS) balancing Domain Name Server (DNS) balancing One DNS = multiple IP addresses One DNS = multiple IP addresses Software/hardware balancing Software/hardware balancing Request at one IP address is distributed to multiple servers Request at one IP address is distributed to multiple servers Reverse proxy Reverse proxy Intercept client request and cache response Intercept client request and cache response

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 19 Client-Side Extensions Add functionality to the browser Add functionality to the browser Plug-ins Plug-ins Hardware/software modules that extend browser capabilities by adding features (e.g. encryption, animation, wireless access) Hardware/software modules that extend browser capabilities by adding features (e.g. encryption, animation, wireless access) ActiveX ActiveX Microsoft COM/OLE components that allow data manipulation inside the browser Microsoft COM/OLE components that allow data manipulation inside the browser Cookies Cookies Block of data stored at client by Web server for later use Block of data stored at client by Web server for later use

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 20 Components for Dynamic Web Sites DBMS–Oracle, Microsoft SQL Server, Informix, Sybase, DB2, Microsoft Access, MySQL DBMS–Oracle, Microsoft SQL Server, Informix, Sybase, DB2, Microsoft Access, MySQL Web server–Apache, Microsoft IIS Web server–Apache, Microsoft IIS Programming languages/development technologies–ASP.NET, PHP, ColdFusion, Coral Web Builder, Macromedia’s Dreamweaver Programming languages/development technologies–ASP.NET, PHP, ColdFusion, Coral Web Builder, Macromedia’s Dreamweaver Web browser–Microsoft Internet Explorer, Netscape Navigator, Mozilla Firefox, Apple’s Safari, Opera Web browser–Microsoft Internet Explorer, Netscape Navigator, Mozilla Firefox, Apple’s Safari, Opera Text editor–Notepad, BBEdit, vi, or an IDE Text editor–Notepad, BBEdit, vi, or an IDE FTP capabilities–SmartFTP, WS_FTP FTP capabilities–SmartFTP, WS_FTP

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 21 Figure 10-3 Dynamic Web development environment

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 22 Figure 10-4 Sample PHP script that accepts user registration input a) PHP script initiation and input validation (Ullman, PHP and MySql for Dynamic Web Sites, 2003, Script 6.6)

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 23 Figure 10-4a (cont.)

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 24 Figure 10-4 Sample PHP script that accepts user registration input b) Adding user information to the database

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 25 Figure 10-4 Sample PHP script that accepts user registration input c) Close PHP script and display HTML form

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 26 Web Services XML-based standards that define protocols for automatic communication between applications over the Web XML-based standards that define protocols for automatic communication between applications over the Web Web Service Components: Web Service Components: Universal Description, Discovery, and Integration (UDDI) Universal Description, Discovery, and Integration (UDDI) Technical specification for distributed registries of Web services and businesses open to communication on these services Technical specification for distributed registries of Web services and businesses open to communication on these services Web Services Description Language (WSDL) Web Services Description Language (WSDL) XML-based grammar for describing Web services and providing public interfaces for these services XML-based grammar for describing Web services and providing public interfaces for these services Simple Object Access Protocol (SOAP) Simple Object Access Protocol (SOAP) XML-based communication protocol for sending messages between applications via the Internet XML-based communication protocol for sending messages between applications via the Internet Challenges for Web Services Challenges for Web Services Lack of mature standards Lack of mature standards Lack of security Lack of security

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 27 Figure 10-5 A typical order entry system that uses Web services (adapted from Newcomer 2002, Figure 1-3) Figure 10-6 Web services protocol stack

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 28 Figure 10-7 Web services deployment (adapted from Newcomer, 2002)

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 29 Service Oriented Architectures Collection of services that communicate with each other by passing data Collection of services that communicate with each other by passing data Web services, CORBA, Java, XML, SOAP, WSDL Web services, CORBA, Java, XML, SOAP, WSDL Loosely coupled Loosely coupled Interoperable Interoperable Using SOA results in increased software development efficiency (up to 40%) Using SOA results in increased software development efficiency (up to 40%)

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 30 Semantic Web W3C project using Web metadata to automate collection of knowledge and storing in easily understood format W3C project using Web metadata to automate collection of knowledge and storing in easily understood format Structuring based on: Structuring based on: XML XML Resource Description Framework (RDF) Resource Description Framework (RDF) Web Ontology Language (OWL) Web Ontology Language (OWL)

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 31 Rapidly Accelerating Internet Changes Integrated database environments Integrated database environments Use of cell phones and PDAs Use of cell phones and PDAs Changes in organizational relationships Changes in organizational relationships Globalization Globalization Challenges to IT personnel require: Challenges to IT personnel require: Business and technology infrastructure understanding Business and technology infrastructure understanding Leadership and communication skills Leadership and communication skills Upward influence techniques Upward influence techniques Employee management techniques Employee management techniques

Chapter 10 © 2009 Pearson Education, Inc. Publishing as Prentice Hall 32 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Printed in the United States of America. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall