Three light-weight execution engines in Java for web data-intensive data source contents : (extended abstract)

Title from cover. "March, 1998."Includes bibliographical references (p. 8-9).Ricardo Ambrose ... [et al.]

The Evaluation of Content-Based Web Queries

We introduce the notions of syntactically and semantically structured data to refine the notion of semi-structured data. As we will see, most data found on the Web is syntactically structured. In order to evaluate content-based Web queries, semantically structured data is needed. The problem occurs to transform syntactically structured data into semantically structured data. Syntactically and semantically structured data can be represented by trees. Our main contribution is a powerful restructuring mechanism that allows to express the transformation of trees representing syntactically structured data to trees that represent semantically structured data. We embed our restructuring mechanism into RAW (Relational Algebra for the Web) and demonstrate its expressiveness by several example queries

Cost-benefit Analysis of Web Bag in a Web Warehouse

Sets and bags are closely related structures and have been studied in relational databases. A bag is different from a set in that it is sensitive to the number of times an element occurs, while a set is not. In this paper, we introduce the concept of a Web bag in the context of a World Wide Web warehouse called WHOWEDA (WareHouse Of WEb DAta) which we are currently building. Informally, a Web bag is a Web table which allows multiple occurrences of identical Web types. A Web bag helps one to discover useful knowledge from a Web table, such as visible documents or Web sites (i.e. documents/sites which can be reached by many paths), luminous documents (i.e. documents with many outgoing links) and luminous paths (i.e. frequently traversed paths). In this paper, we provide a cost-benefit analysis of materializing Web bags as compared to Web tables with distinct Web tuple

YAXQL : A powerful and web-aware query language supporting query reuse and data integration

Since XML seems to be the next great wave on the web, several query languages for XML have been proposed. Unfortunately, none of these proposals comes even close to meet the requirements for such a query language. We review the requirements for a query language for XML and propose a new query language, YAXQL, which meet them

Automatic Migration of Files into Relational Databases

ABSTRACT In order to provide database-like features for files, particularly for searching in Web data, one solution is to migrate file data into a relational database. Having stored the data, the capabilities of SQL can be used for querying, provided, the data has been given some structure. To this end, an adapter must be implemented that converts data from files into the database. This paper proposes a specification-based automation for this procedure: Given some descriptive specification of file contents, those file adapters are generated. An adequate specification language provides powerful concepts to describe the contents of files. In contrast to similar work, directory structures are taken into account because they often contain useful semantics