Integrating the Access to Documental Databases on the Web

This work presents a proposal of architecture for a system designed to provide a uniform access through Internet to different distributed and heterogeneous documental databases, which in our case will store antique Spanish documents and information about them. Our main goal is to offer an intuitive interface, designed using the ideas of Virtual Book and Virtual Library metaphors. This interface should let the user ask complex queries with a total transparency about where the databases are, which ones are needed, and how their conceptual scheme, DBMS and query languages are. The architecture we propose is composed of four wellisolated levels, thus easily allowing for the scalability of the system: the first one is a unique user interface to access all databases; a second level that distributes the queries and integrates the answers; a third one that deals directly with the databases; and the databases themselves. So far we have developed an interface to access a database that stores a corpus of Spanish Emblem Literature. We propose the use of XML (eXtended Markup Language) to define a Formal Query Language (XMLFQL) and a Formal Answer Language (XML-FAL) that will provide the needed independence between the databases and the other layers of the system. For the query interface, Virtual Book and Virtual Library metaphors are used to allow the users to express sophisticated queries. In addition, Bounded Natural Language sentences are used in order to provide a flexible, powerful and easy to use interface.