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The interface MsqlPerl takes up of the integration between the database mSQL engine and the
client WWW, overpassing the monitor program included on the package. The interface MsqlPerl
simplifies the management and queering in the database mSQL thanks to the Language Perl (Practical
Extraction and Report Language) designed by Andreas Koenig at the University of Berlin.
It is worth noting that MsqlPerl and mSQL are shareware software, thus free and distributed (not
for commercial purpose).
WWW and mSQL are essential tools for providing facilities in distributing and sharing metadata
with an high level of interaction among database users.
The interface has been implemented according a logical scheme (fig. 2) with the following
characteristics:
- data are fetched in the Database and they are transferred in the Web page;
- the web page is designed in such a way that it is not only a static display but it works as a hypertext able
to link to other Databases or Applications.
In short WWW works as a client of mSQL as well as a server HTTP for the outside.
In this way the Metadati Database on the Venetian Lagoon is made available and accessible to
any user via Internet and it can be managed and updated from even - point connected to Internet.
6. THE QUERY INTERFACE OF DATABASE FROM WEB
A web site on the Lagoon of Venice is now available at the University of Venice "Ca' Foscari".
From the home page, clicking Metadata, a query form to the database appears. It is an active page
displaying 6 fields for querying: card number; key words, institution, geographic coverage, scale, theme.
After filling one or more than one fields and clicking "cerca". the search into the database starts.
Some priorities have been introduced:
- the card number has an absolute priority avoiding to cross with the other fields and the result displayed
is the table of "general data" of the card requested:
- the theme has a priority with regards to the other fields in the sense that the search result is a table of all
themes found.
From the result-pages of the search it is possible to go through an hypertextual link to all
information concerning a given card or theme. This is made possible thanks to the database interface
designed so that to display a set of web pages, dynamically generated by special procedures which allow
to navigate into the structure of metadata database.
7. CONCLUSIONS
Our expenence in collecting this sample of metadata points out a number of issues related to the
lack of awareness about the value of the information.
We observed some points:
- difficulty of people in answering to metadata questionnaire for many reasons;
a) habit not to communicate data;
b) unaware of terminology describing data.
- lack of a policy in reporting the methodology of acquisition of data.
It resulted that many parts of the questionnaire have not been completed. In the Database we
implemented also these fields hoping to sensibilize people to report in their next studies metadata
information.
The web solution we present here give a new value to the Metadata information which can be
supplied and consulted everywhere
This facility eliminates every' temporal delay allowing people to have a timely information.