SCHEMA-BASED AUTHORING AND QUERYING OF LARGE HYPERTEXTS

Modern hypertext applications require new system support for hypertext authoring and user navigation through large sets of documents connect ed by links. This system support must be based on advanced, typed data models for describing the information structure in different applicat ion domains. Schema based structuring through strongly typed documents and links has already been proposed and put to practical use in a mul titude of hypertext applications. Systems such as Multicard/O-2 and MO RE have moreover exploited conceptual schemas for querying the resulti ng hyperdocuments in a more structured way. In this paper, we show how hypertext schemas and query languages can be utilized for designing h ypertext authoring and browsing environments for large hypertexts. We illustrate our mechanisms using the Gram data model and describe their implementation on top of the Multicard hypermedia system connected to the O-2 object-oriented database management system. (C) 1995 Academic Press Limited