3 . 5 The Database View
Let's move now to an examination of the relationship of documents to databases. Documents can relate directly to databases in two main ways. First, as the report or simple printout of a database. This is known as database publishing. Second, and more interesting, is the use of a database to hold the document content. The various components that comprise a document can be placed into a database. The database can be queried by the publishing system and out pops the printed pages (if only it were that simple). These types of systems are possible today; however, there are no hard and fast rules for accomplishing such implementations. Each organization's needs and requirements must be carefully analyzed, and no one solution will fits everyone's needs.
Reusing a document's components is becoming increasingly possible. Reuse is possible only if you can identify and reassemble pieces of content. Mechanisms to break apart the original document into meaningful component parts can be developed using standards and well-defined recommended practices. Reuse is also another potential benefit for the use of a document structuring standard like SGML.
Sometimes the seemingly simple task of finding the relevant material may, in fact, be the most difficult aspect of reusing content material. Document repositories must be created with appropriate key words or embedded tagging mechanisms that enable meaningful retrieval. Electronic imaging systems, which scan reams of documents and store the images on optical disks as a replacement for microfilm, are a growing industry. Without sufficient tagging, these systems are a small step forward from microfilm technology. An image of a page without the means of asking for information about what is on the page is no better than a picture. About the only savings is in physical storage space (which may, in fact, be significant for an organization).
3 . 5 . 1 Database Publishing
An extension of reportgeneration capabilities, which has been around for many years, database publishing adds a level of integration between the database and the publishing system. A report is one visual representation of a database. Slick publications produced by pouring data into visual templates might be another representation of the same database.
Database publishing tools allow you to choose particular fields in a database for printing. Particular styles can be applied to these fields and selectively printed. Such tools are invaluable for catalogs with thousands or hundreds of thousands of entries, such as a yellowpages directory and parts catalogs, which must be updated regularly. Information from inside the database is extracted and combined with the publishing system to produce goodlooking documents, not simply printouts.
The most common form of database publishing involves merge facilities. A merge facility combines regularly structured information with a template document. For example, a list of names and addresses, one per line with tab separators, might be combined with a form letter that contains special codes that indicate, to the document processor, when to insert data from the data file.
A tighter link between the database (information source) and the document (information sink) aids the communication process in several ways. Information in a database will eventually need to be explained, summarized, and otherwise communicated to someone. With a link the information can reach the document faster and with fewer potential errors. Translations and transcriptions of database information to documents are errorprone tasks; the more direct this process can be, the better.
If you take the concepts of database publishing one step farther, you arrive at the concept of a document that functions as a front end to a database. The information in a document that came from a database can serve as the interface to a database. Database queries via the document and automatic updates bring the database/document connection full circle. Live link and active documents provide the technological foundations for a tight linkage.
3 . 5 . 2 Customized Publishing
If a collection of informationthe content of a documentis kept in the proper type of database, publishers can reuse the content and create customized texts. Hardware and software advances are both contributing to a new publishing technology, that enables documents to be custom made for particular audiences.
In 1990, a partnership between McGraw-Hill and the University of Southern California was described as follows:
Textbook publishers are offering new computer and printing systems that allow professors to custom-design textbooks by handpicking course materials from electronic databases stocked with traditional textbooks, magazine articles, and other published information.
These customized books can be printed in limited quantities by the campus bookstore and distributed to students, sometimes within hoursnot weeks or monthsafter ordering.(18)
One enterprising Washington, D.C., based company is taking another direction in custom printing. You might call it "just-in-time" printing. It produces an hourly newspaper, called "The Latest News," for people who travel the Washington to New York air shuttle.(19) Information from wire services is fed into document processing systems and formatted right away. This approach blurs the line between printed media and radio.
The ultimate in customized publishing is represented by some of the research at MIT's Media Lab. One interesting project unites information from wire services and television news. Using a computer screen with a touch screen interface, the reader can interact with this "newspaper." Fingering topics brings articles into view, touching a color picture can bring it to life as video. This work and other projects at the Media Lab are pointing the way to personalized interactive information sources beyond the newspaper...but I'd still like to read it in bed.(20)
Finally, to no one's surprise, the Web, the great technology integrator, provides ample example of interactions with and publications of databases. The most common use of database publishing on the Web are the Internet Searching starting points, (see section 1 . 9 Internet Starting Points) that allow users to query the database. The result is an instant database publication of the search results.
A great example of customized publications is the ability to customize your own starting page when using Microsoft's Web browser, the Internet Explorer. The Internet Explorer lets you pick a set of favorite linksnational or world news, weather, comics and television listingsand have them displayed on your starting page. Of course, you must have the Microsoft Network set as the "home" page for this to work, but it's a compelling feature.
