web-based databases

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School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions LIS 386.13 Information Technologies and the Information Professions Web-Based Databases R. E. Wyllys Last revised 2003 Apr 22

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Page 1: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

LIS 386.13 Information Technologies

and the Information Professions

Web-Based Databases

R. E. WyllysLast revised 2003 Apr 22

Page 2: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

Lesson Objectives

• You will– Understand the four main types of uses of

databases on the World-Wide Web– Become familiar with some of the tools and

techniques involved in developing Web-based databases (WBDBs)

Page 3: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

What Do WBDBs Do?• What are the purposes for which WBDBs are

used? Feiler (1999) distinguishes four main purposes:– "Publishing data on the Web."

• "Here, you use the Web as a publication tool; browsers interact with dynamic hypertext markup language [DHMTL], application servers, and database queries to present the information as requested. The data flow is one way: from the database to the user."

– "Sharing data on the Web." • "In this scenario you use databases and the Web to share

data among people; the data flow is bidirectional—some people enter data, other people look it up."

Page 4: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

What Do WBDBs Do? (cont'd)

– "E-commerce." • "This area includes all online commercial transactions.

Although the data flow is bidirectional, it typically consists of a relatively large amount of data that flows from the database to the customer (during the shopping and evaluation steps); that is followed by a relatively small amount of data that flows from the customer to the database as the sale is consummated."

– "Totally database-driven Web sites." • "You can use databases to generate Web pages and

keep them up to date. In this case, the database is usually invisible to the user; it is a behind-the-scenes assistant to a Web site."

Page 5: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

WBDBs Used for Publishing on the Web• Here are some examples, from A to Z, of WBDBs whose primary purpose is publishing

information. I recommend that you look at these WBDBs bearing that purpose in mind, and that you think about how they succeed or fail in achieving the purpose.– WBDBs on astronomy

• The Space Telescope Science Institute offers pictures taken by the Hubble Space Telescope and other information on astronomy

• The Planetary Society is an organization that promotes exploration of the solar system. Its Website offers news about current and prospective exploratory activities

– WBDBs about automobiles• Edmunds.com is primarily a DB for publishing information about automobiles (although it also

maintains a forum for exchanges of information and opinions)• National Highway Traffic Safety Administration; its name explains it• Insurance Institute for Highway Safety; its name explains it

– WBDBs for library and information science• American Society for Information Science and Technology provides both information and

links• Association of Information Management Professionals (formerly, Association of Records

Managers and Administrators) provides both information and links

Page 6: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

WBDBs Used for Publishing (cont'd)– WBDBs for library and information science (cont'd)

• American Library Association main page– ALA Resources for Parents, Teens and Kids provides links, in itself a form of publishing

information*– Libraries, Children & the Internet Questions & Answers provides both information and links*– Teen Hoopla: An Internet Guide for Teens provides both information and links*

• Music Library Association provides both information and links• National Archives and Records Administration provides Access to Archival Databases, a

research tool that makes a selection of the Archives' most popular electronic records available to the public over the Internet

• Society of American Archivists provides both information and links• Special Libraries Association provides both information and links• Texas Library Association provides both information and links

– WBDBs on various subjects• Consumer Reports Online provides ratings of goods and services, along with general advice

on personal finance and product safety• Dilbert.com provides access to the Dilbert comic strip• Flags of the World is a WBDB about vexillology, the study of flags

*I am indebted to Ms. E. Joanmarie Marks for suggesting these sites.

Page 7: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

WBDBs Used for Publishing (cont'd)– WBDBs on various subjects (cont'd)

• frankandearnest.com offers access to the Frank and Earnest comic strip (with some of the world's best puns)

• Hoaxbusters, "a public service of the CIAC and the U.S. Department of Energy" exposes Internet hoaxes

• Iceland offers a wide variety of information about Iceland• InternetNews.com provides news about the Internet, especially about commercial activities• Scientific American offers information on science and access to experts in many scientific

fields• The Texas Records and Information Locator (TRAIL), of the Texas State Library, provides

access to Texas state agencies and information sources.• The U.S. Postal Service Rate Calculator enables you to calculate the postage required on

letters and packages, both domestically and internationally.

– WBDBs on zoology• University of Michigan Zoology Museum; its name explains it• World Lecture Hall—Zoology, UT-Austin provides links to lectures, pictures, and divers

sources of information on zoology

Page 8: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

WBDBs Used for Publishing (cont'd)• Other kinds of WBDBs whose primary purpose can be viewed as

publishing (after finding) information include search engines and online public-access catalogs

• Web-Search Engines maintain enormous DBs about the contents of Websites. Some examples: – AltaVista Advanced Search– C'est Trouvé specializes in information in French– Google– Infobel and InfoSpace offer directory information for people and businesses– InfoSel offers search capabilities and news about Mexico and other parts of

Latin America– Northern Light– Suchmaschine.com specializes in information in German– Yahoo!

Page 9: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

WBDBs Used for Publishing (cont'd)• Many libraries provide online access to their holdings via online public-access catalogs (OPACs).

Clearly, OPACs are WBDBs. Some examples:– The Austin Public Library Catalog– The Catálogo de la Biblioteca Daniel Cosío Villegas of El Colegio de México

• Note: This appears to be inaccessible with Netscape; use Internet Explorer.

– The Catálogo de Recursos de Información del Centro de Información-Biblioteca of the Instituto Tecnológico y de Estudios Superiores de Monterrey (ITESM)

– The Catalogue BN-OPALE-PLUS of the Bibliothèque Nationale Française. (After you reach the hyperlinked page, click on "Connexion au catalogue". You should experiment with both the Recherche Simple and the Recherche Combinée.)

– The Catalogue of the National Library of Australia– The Harvard OnLine Library Information System (HOLLIS) of Harvard University– The Library of Congress Online Catalog– The OPACs of the University of California, Berkeley (GLADIS) and the University of California System

(MELVYL) are both available via Library Online Catalog Systems– The UTNetCat of the UT-Austin General Libraries

• I recommend that you visit all these online catalogs, do a search in each, and compare the techniques that the catalogs offer and the results they yield. You will find interesting similarities and interesting differences.

Page 10: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

WBDBs Used for Sharing Data• Forums and Chat Rooms typify the WBDBs that are using for sharing data and

information (and often misinformation). These uses are characterized by a two-way flow of information and data between the user and the WBDB, with the user typically supplying a substantial part of the flow. Some examples:– CSICOP Chat Room, of the Committee for the Scientific Investigation of Claims of the

Paranormal– Edmunds.com Town Hall Community, "where smart car shoppers talk about cars, trucks and

related consumer issues" (the forum of Edmunds.com) – Straight Dope Message Board, a forum for discussing topics related to Cecil Adams's

syndicated column, "The Straight Dope"– Teens Chat and Hang-Out Home Page, a chat room for teenagers– ThirdAge, a forum for seniors to "meet & talk"– Upper Valley Materials Exchange, which “links businesses and community members who

have surplus furniture, supplies, materials, equipment, etc. with schools (and other non-profits) in the Upper [Connecticut] Valley that have a use for them"

• And, of course, any of the 59,000+ Usenet Groups can be regarded as a WBDB for sharing data (or at least opinions) and, lamentably often, for solicitations from businesses and services, pornography, etc.

Page 11: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

WBDBs Used for E-Commerce• As you are undoubtedly already aware, an enormous number of

Websites are devoted to commercial activities, also characterized by a two-way flow of information and data between the user and the WBDB, with the user supplying only a limited part of the flow. As examples, we can mention four Websites that deal with books, both new and second-hand:– Alibris.com– Amazon.com – BarnesandNoble.com– Powells.com – Note: Each of the above sites is slightly different from the others. You should

compare each of them against the others with respect to their design, organization, and means of obtaining information from their users.

Page 12: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

WBDBs Used to Drive Websites

• Some WBDBs serve to keep Websites constantly up-to-date with current information. A few examples:– CNBC.com, financial news from National Broadcasting Company– CNN.com, general news from Cable News Network (CNN)– CNNFN.com, financial news from CNN

• Note: I recommend your comparing CNBC and CNNFN. Though they target exactly the same audience, their designs and organization are somewhat different.

– Greenwich provides the exact time (at the moment you open its Webpage), along with information about time-keeping

– The current weather in any of 10,000 cities is available from CNN Online: e.g., click here, Austin, for the weather in Austin

– Weather.com, the Web version of the Weather Channel on cable television, provides a variety of weather information

• Note: Again I recommend your comparing CNN's and the Weather Channel's displays of local weather information.

Page 13: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

Techniques for Developing and Maintaining WBDBs

• The WBDBs discussed in the foregoing slides have to be developed and maintained. The methods involved in doing so can be highly technical, so we shall merely sketch herein some general ideas about these methods.– Underlying all WBDBs is a relational database-management

system (RDBMS), together with one or more relational databases (RDBs) that actually contain the data or information of interest

– A Webpage defined in HTML or Dynamic HTML (DHTML) controls the visual display that the user of the WBDB sees.

– An interface (1) receives information from the user and passes it to the RDBMS, (2) extracts information from the RDB (with the assistance of the RDBMS), and (3) provides the information to the Webpage, whose HTML or DHTML structure makes the information visible.

Page 14: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

Techniques for Developing and Maintaining WBDBs (cont'd)

• RDBMSs used for WBDBs– Although Microsoft Access 97 (and later versions)

offer built-in support for WBDBs, the limitations of MS Access restrict it to Websites that experience small levels of use (no more than a few simultaneous users).

– Large and heavily used WBDBs typically use high-level RDBMSs such as IBM DB2, Informix, Microsoft SQL Server, Oracle, and Sybase. A substantial majority of such sites use Oracle.

Page 15: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

Techniques for Developing and Maintaining WBDBs (cont'd)

• The interfaces used for WBDBs fall into two broad classes– Interfaces intended for a specific application and written

in a scripting language that conforms to Common Gateway Interface (GCI) standards

• A script is a set of programming-language statements, typically (but not necessarily) short and used to accomplish certain actions on the Internet

• Languages used in scripts include C, C++, Java, Perl, and Visual Basic for Applications

– Interfaces developed commercially for a certain class of applications

• Commercial interfaces include those of Oracle, SAP, and Siebel.

Page 16: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

Techniques for Developing and Maintaining WBDBs (cont'd)

• A popular tool for aiding in the development of CGI scripts is ColdFusion. – You can think of ColdFusion's role in working with CGI scripts as analogous

to that of Dreamweaver and Microsoft FrontPage in aiding the preparation of HTML-formatted pages.

– P. Mohseni (1996, p. 238) describes ColdFusion as having the capabilities to• "Insert and update records in database tables with HTML forms• "Submit database queries that can then be used to dynamically generate Web

pages• "Intermix the results of queries with HTML tags and text for complete control over

how data is displayed and formatted• "Track users and customize their view of Web pages by using information about

their browser, location, or other preferences• "[Use a]dvanced data input and reporting features• "Validate form field entries as integer, floating point, date or numeric range

Page 17: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

Techniques for Developing and Maintaining WBDBs (cont'd)

– ColdFusion capabilities (cont'd) • "Make conditional statements (if . . . else branching) to

dynamically customize output returned to users and decisions about queries submitted to the database

• "Embed SQL statements in templates to specify queries. SQL statements may be dynamically customized using data from from submissions, URL query strings, and CGI environment variables, as well as the results returned from other queries

• "Execute multiple SQL queries and send SQL queries to multiple databases for each client request

• "Support Java and JavaScripts• "Support Netscape cookies for state control"

Page 18: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

Electronic Customer Relationship Management (eCRM)

• An example of the use of interface software tailored for a class of applications is what is known as "Electronic Customer Relationship Management" (eCRM) software.

• J. Killelea (2001) describes the general nature of eCRM as follows:– "A database pulls together customer data—purchases,

demographics and preferences—from various sources, such as websites, transaction systems and call centers.

– "Data is segmented according to set criteria—frequent shoppers, attributes of shoppers, location of shoppers—and personalized for products and services.

Page 19: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

Electronic Customer Relationship Management (eCRM) (cont'd)

• The general nature of eCRM (cont'd)"Based on personalized information, customers receive

promotional material—sales, new products and services—via the website, email, snail mail or phone.

– "Customers respond to promotional offers by making a purchase, inquiring about a product or seeking customer service. This information is sent back to the database and the process begins again."

• Vendors of eCRM software include Accrue Software, Broadbase Software, E.piphany, and Informatica.

Page 20: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

Electronic Customer Relationship Management (eCRM) (cont'd)

• B. B. Tulsi (2001) offers an interesting example of how eCRM technology can work in medical practice.– "E-health companies make it possible for doctors to write or

refill prescriptions in about 20 seconds using their cell phones, PDAs [personal digital assistants] or dedicated wireless devices. This not only saves time for the doctors and pharmacists, it prevents miscommunications and avoids mistakes.

– "[The d]octor uses his cell phone, PDA or dedicated prescriber to look up information on a patient, enter his diagnosis and make drug selections

– "The wireless device is linked to an onsite server

Page 21: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

Electronic Customer Relationship Management (eCRM) (cont'd)

• eCRM technology in medical practice (cont'd)– "The server connects to a database that tells which

medicines are allowed under the patient's insurance plan. It will also indicate if the prescribed drug will cause a reaction with any other medication the patient is currently taking.

– "Once everything checks out, the server faxes a prescription to the patient's pharmacist, which might be a retail, mail order or online outlet."

• Note: Currently eCRM software is much too expensive for use in academic, public, or school libraries. But as it decreases in price, interesting possibilities will be opened for using such software in libraries and other information agencies.

Page 22: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

Summary• We have looked at Web-based databases and at how

they are used, developed, and maintained.• It seems entirely safe to predict that

– WBDBs will become increasingly prevalent and increasingly sophisticated in the ways they receive (and sometimes extract, as with "cookies") information from users, as well as in the ways in which they display information to users.

– Though the most sophisticated uses of WBDBs are currently found in the commercial arena, such uses will spread steadily into the non-profit and other less well financed arenas.

Page 23: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

Web-Based Databases Cover the World

Page 24: Web-Based Databases

School of Information - The University of Texas at Austin LIS 386.13, Information Technologies & the Information Professions

References• Antelman, Kristin. Getting Out of the HTML Business: The

Database-Driven Web Site Solution. Information Technology and Libraries. 1999 December; 18(4): 176-181

• Feiler, Jesse. Database-Driven Web Sites. San Francisco, CA: Morgan Kaufmann; 1999. ISBN:0-12-251336-3.

• Killelea, Jim. Electronic Salesmen Score More Sales Per Customer. Technology Investor. 2001 January; 1(11):18-20

• Mohseni, Piroz. Web Database Primer Plus: Connect Your Database to the World Wide Web Using HTML, CGI, and Java. Corte Madera, CA: Waite Group; 1996. ISBN:1-57169-070-0

• Tulsi, Bernard B. E-health Whacks Waste Away—$600 Billion a Year. Technology Investor. 2001 January; 1(11):22-25