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                                    DELPHI-ISIS: A new front-end for CDS/ISIS databases
                                                         under Windows 95/NT
                                                                    L J Haravu

INTRODUCTION

The availability of CDS/ISIS since 1986 free of charge to the developing world has enabled many libraries and documentation centers to develop useful databases. Some of these databases are available on network servers and also on World Wide Web (WWW) sites for interactive access by end-users.

Problems faced by end-users as opposed to information specialists in using DOS version of CDS/ISIS are:

* The menu-driven nature of CDS/ISIS is not always easy to use. The user has to navigate through several menus to obtain  information. The user is constrained by a lack of integration of browsing; search formulation, display, formatting and output production functions often sought in an information retrieval system.

* There is little or no help provided to end-users in their use of the software.

* The increasing availability of graphical user interface (GUI) based software under the Windows 3.1, 3.11, Windows 95 and Windows NT operating systems during the 1990's and the fact that such software have a common look and feel across different applications, has made such software the sought after model by end-users. This is primarily because the learning curve for such software is short one compared to what it takes to become familiar with DOS-based software.

Some attempts were made during the 1990's to build front-ends to CDS/ISIS databases to emulate GUI-based software. One example was the Heurisko front-end developed in Italy and distributed by UNESCO to users. However none of these came close to the friendliness and functionality of Windows-based software. Examples of such software became available with software provided for searching CD-ROM databases.

UNESCO took upon themselves the task of building a Windows version of CDS/ISIS. The version called WINISIS under development for over 3 years was officially released only in 1998.

The development of DELPHI-ISIS being reported in this article is another attempt to provide a GUI-based front-end to        CDS/ISIS databases.

DELPHI-ISIS

DELPHI-ISIS has used Borland Corporation's Rapid Application Development tool (RAD tool) called DELPHI. RAD tools became popular during 1992 with the introduction of Visual Basic, Power Builder and later DELPHI. These tools are visual      programming interfaces and are based on the Object-Oriented Programming (OOP) language paradigms. These  tools facilitate the development of event-driven interfaces, typical of Windows-based applications as opposed to menu-driven interfaces that    were typical of DOS-based  applications. Before the appearance of RAD tools, programmers had to write Windows applic-
ations using initially the C language and later OOP languages such as C++. RAD tools provide greater ease in developing Windows applications, because such tools enable the developer to concentrate on providing the functionality rather than being overly concerned with the visual aspects of the application. Further, RAD tools facilitate the reuse of code and visual elements (e.g. a Form) and events associated with visual elements of an application.

DELPHI-ISIS has also used a dynamic link library (DLL) called ISIS32.DLL developed by UNESCO and the Brazilian Institute of Health Sciences (BIREME). The DLL encapsulates functions, which are specific to CDS/ISIS. For instance, the DLL has functions for searching CDS/ISIS databases, for retrieval of CDS/ISIS records given its Master File Number (MFN), for invoking a predefined display format, etc. An important advantage of DLL's is that the functions declared in the DLL are callable by programs written in C++, Visual Basic, and DELPHI. Also, by using DLL's, programmers can reuse the code of a  third party to provide the needed functionality without reinventing the wheel. Another advantage of DLL's is that the called  functions are linked to the calling program, dynamically, i.e., at run time rather than statically, as was the case in the past.

DELPHI-ISIS was developed as a front-end to CDS/ISIS databases with the end-user in mind as opposed to its use by librarians and information specialists. The idea was to make available a tool which is more user-friendly than the menu-driven   front-end.

DELPHI-ISIS CAPABILITIES

DELPHI-ISIS has used the Single Document Interface (SDI) model for its development. This means that the user has access to entire search, browse, display, saving, printing, and downloading functions in a single window. For the user, it means  that he does not have to negotiate his way through different menus. Very importantly, the user has concurrent access to search history, retrieved records, dictionary of search terms and ANY terms. These features provide the user with greater control over the        search process as compared to earlier approaches in menu-driven applications.

An important advantage of most GUI-based applications including DELPHI-ISIS is the fact that user input to accomplish a task is kept to a minimum. In DELPHI-ISIS, the user mostly needs to click on menu options, buttons, or dictionary terms, or if he is happy with doing so, he can drag and drop search terms. The user can thus concentrate on the strategy and content of his retrieval rather than on the mechanics of the search formulation process and problems (e.g., miss-spelled words when data entry is involved).

An important advantage of DELPHI-ISIS is the availability of hypertext based help. The Windows Help file that comes as an  integral part of the application has been built specifically for the specialist user. The help file contains information that hopefully instructs the user on how to search CDS/ISIS databases apart from using the features specific to DELPHI-ISIS.

DELPHI-ISIS can be used to search one or more databases on one or more devices; local hard disk, network server,  CD-ROM drive. Data from one or more databases can be used to produce needed outputs.

Importantly, DELPHI-ISIS provides  the facility for the user to customize his outputs by allowing him to choose only those fields he wants in his output. Outputs can also be specified to have short labels, long labels, or field tags. Alternatively, the user may specify the use of predefined CDS/ISIS formats for display or output production. The fact that users can customize their     outputs is important because it is then possible for users to import the results of a search using DELPHI-ISIS into one or other database system, e.g., dbase III+ or FoxPro.

DELPHI-ISIS also provides the user the facility to save search history and later recall the saved search history for its execution on the same database or another database. Another feature of DELPHI-ISIS is the possibility to use words or phrases in retrieved records to refine the search. Also, DELPHI-ISIS enables a search for a specific string of characters within a set of retrieved records.

DELPHI-ISIS is a 32-bit application and provides considerably faster access to CDS/ISIS databases as compared to 16-bit applications written for Windows 3.1 and 3.11. Lastly, DELPHI-ISIS can be used both on stand-alone machines and on networks. It has been tested on Novell, Windows-NT and Digital's Pathworks based networks.

DELPHI-ISIS LIMITATIONS

The present version of DELPHI-ISIS does not support CDS/ISIS display formats with embedded calls to Format Exits (small   Pascal programs). This is a limitation of the ISIS32.DLL. If an attempt is made to use a display format with a Format Exit, DELPHI-ISIS flags an error and allows the user to choose an alternative format.

Another limitation is related to the use of ANY Search terms. Although the version does permit the use of and searching of ANY terms, the software cannot handle very large ANY terms. If search of an ANY term with many postings is done,         DELPHI-ISIS hangs up. This is apparently a limitation of the ISIS32.DLL.

FUTURE DIRECTIONS

Search formulations in the present version expects that the user is familiar with using the dictionary, using Boolean operators and
field-specific searching. This may not always be true. A novice-friendly search interface is planned for a future release of          DELPHI-ISIS. The idea is to provide a form-based interface that will enable the  user to progressively build his query and also
to test it during the process of building it. It is believed that such a facility would enable users to become more adept at  searching and obtain better search results.

Another feature planned for a future release of DELPHI-ISIS is the capability of export records into a variety of formats, e.g., as comma-delimited files. The idea is to enable users to download data from a CDS/ISIS database using DELPHI-ISIS and then to import such data into a personal information system that they may be using.

AVAILABILITY OF DELPHI-ISIS

DELPHI-ISIS comes on a single diskette with an install feature making it easy for users to install the software and configure it   for their machines. A zip file of a demo version of DELPHI-ISIS is available at the web site, http://members.aol.com/vharavu/  delphi2, and the file to download is DELISIS.ZIP. Once this file is downloaded and unzipped, run the Setup.Exe to install the software. The demo version has all the functionalities of the full version but will work with databases of upto 1000 records.

The full version of the software is available at a small cost ($20.00) to interested users and may be obtained from the author at jharavu@hd2. vsnl.net.in or jharavu@hotmail.com

General Comments

* The report seems to be exclusive and very strongly in favor of the views, stand and opinions of a particular set of institutions and organizations like NIC and NASSCOM.(bias)

What NISSAT should be doing about IT?

* NISSAT took about 5 years to collect information on database efforts in India. Of these hardly 3-5% of efforts has seen the light of the day. In order to make such efforts widely deliverable and accessible, there is a strong need and commitment to support the development and privatization of information products and services in electronic mode.

* Recognizing the need for community information services to construction sector, a request came through seeking NISSAT support. This sector has 45-50% of the total plan outlay and is 2nd largest industry to provide employment to masses.

* During the first national meet at Suraj Kund, Haryana an effort was made to form an information industry association which could not take shape. However, going by the phenomenal developments and the limitless, possible opportunities for the nation, it becomes urgent that the `Content Creation Consortium' is formed in this 4th ITT Meet. NISSAT shall endear to work towards the nucleation of this consortium
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