WebOQL: Exploiting document structure in Web queries

grantor: University of TorontoThe widespread use of the Web has given rise to several new data management problems, such as extracting data from Web pages and making databases accessible from browsers, and has renewed the interest in problems that had appeared in other contexts before, such as querying graphs, semistructured data and structured documents. Although several kinds of systems have been proposed to deal with each of these Web-data management problems, none of them addresses all the problems from a unified perspective. Many of these problems essentially amount to data restructuring: we have information represented in a certain structure and we want to construct another representation of (part of) it using a different structure. In this thesis, we present the WebOQL language, which provides a general framework for performing several forms of data restructuring in the context of the Web. WebOQL overcomes a common limitation observed in query languages for the Web, namely the lack of support for exploiting the internal structure of documents; it also synthesizes ideas from query languages for semistructured data and for website restructuring. This thesis formally specifies the syntax and semantics of WebOQL, gives a bound on the complexity of query evaluation and describes the current prototype implementation.M.Sc