Chapter 15In this chapter, you will learn:Web Database ConnectivityTypical Uses of InternetCharacteristics/Benefits of Internet TechnologyCharacteristics/Benefits of Internet Technology (con’t.)Web-to-Database MiddlewareWeb-to-Database MiddlewareWeb Server InterfacesAPI and CGI Web Server InterfacesWeb-to-Database Middleware Connection MethodsODBC to Access DatabasesWeb-to-Database Middleware Uses ODBC to Access DatabasesWeb BrowserColdFusionHow ColdFusion WorksSlide 17ColdFusion TagsColdFusion Dynamic QueryThe Web as a Stateless SystemINSERTs and UPDATEs with ColdFusionDELETEs with ColdFusionInternet Database: Special ConsiderationsSupported Data TypesData SecurityTransaction ManagementDenormalization15Chapter 15Web Database DevelopmentDatabase Systems: Design, Implementation, and Management, Fifth Edition, Rob and CoronelDatabase Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel215In this chapter, you will learn:•How Internet databases are typically used•About the architecture of Web-to-database middleware•How Web-to-database middleware (ColdFusion) is used to integrate databases with the Internet•What special considerations govern Web database developmentDatabase Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel315Web Database Connectivity•Allows rapid response to competitive pressures–New services–New products•Customer support enhanced•Fast effective information dissemination–Universal access–Local –Around the globeDatabase Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel415Typical Uses of InternetTable 15.2Database Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel515Characteristics/Benefits of Internet Technology•Hardware & software independence–Cost savings–Uses existing equipment–Platform independence and portability–No need for multiple platform development•Common simple user interface–Reduced training–Reduced supportDatabase Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel615Characteristics/Benefits of Internet Technology (con’t.)•Location Independence–Global access through Internet–Reduced costs for dedicated connections•Rapid development at manageable costs–Development tools–Low entry costs–Available software & access toolsDatabase Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel715Web-to-Database Middleware•Server-side extension–Interacts directly with Web server–Handles specific requests–Also known as Web-to-database middleware–Examples•ColdFusion•CGI•APIDatabase Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel815Web-to-Database Middleware Figure 15.1Database Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel915Web Server Interfaces•Common Gateway Interface (CGI)–Uses script files to connect to database–Perl, C++, VB•Application Programming Interface (API)–Newer and more efficient–Uses DLLs –Memory resident and faster–Well known APIs•Netscape (NSAPI)•Internet Server API from Microsoft (ISAPI)•WebSite API from O’Reilly (WSAPI)Database Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel1015API and CGI Web Server InterfacesFigure 15.2Database Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel1115Web-to-Database Middleware Connection Methods•Native SQL access middleware•Use services of Open Database Connectivity (ODBC)•Use Object Linking and Embedding Database (OLE DB) interface with Windows•ODBC most commonDatabase Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel1215ODBC to Access DatabasesFigure 15.3Database Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel1315Web-to-Database Middleware Uses ODBC to Access DatabasesFigure 15.4Database Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel1415Web Browser•Located on the client computer •End user Web interface•Interprets HTML code received from Web server•Presents page components in a standard way•Client-side extensions–Plug-ins–Java and JavaScript–ActiveX and VBScriptDatabase Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel1515ColdFusion•Web application server•Uses–Connect and query database from Web page–Present database data in a Web page–Create dynamic Web search pages–Create Web pages to insert, update, and delete data–Define required and optional relationships–Define required and optional form fields–Enforce referential integrity in form fields–Use simple and nested queries to represent business rulesDatabase Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel1615How ColdFusion WorksFigure 15.5Database Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel1715How ColdFusion Works•Server-side markup language–HTML extensions–ColdFusion Markup Language (CFML)•Executed in interpreter mode•Contain HTML, CFML•May contain Java, JavaScript, or VBScript•Client browser requests .cfm page from Web Server–ColdFusion application server executes .cfm script–Sends resulting output in HTML to Web Server–Web server sends to client browserDatabase Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel1815ColdFusion Tags•CFQuery –Queries a database•CFOutput –Displays data returned by query•CFTable–Displays data in Tabular formatDatabase Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel1915ColdFusion Dynamic Query•Create script to generate form with criteria used in database search•Create script to execute query and display results–Uses ColdFusion tags–Uses HTMLDatabase Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel2015The Web as a Stateless System•Web server does not know status of any client at any given time•Request-reply model of communication•Browser concerned only with current page•Data processing requires additional software–Java, JavaScript, VBScriptDatabase Systems: Design, Implementation, & Management, 5th Edition, Rob & Coronel2115INSERTs and UPDATEs with ColdFusion•CFINSERT Tag–Adds records to database–Parameters•DATASOURCE•TABLENAME•CFUPDATE Tag–Updates selected database contents–Parameters•DATASOURCE•TABLENAMEDatabase Systems: Design, Implementation, & Management, 5th Edition,