A Model For Querying Semistructured Data Through The Exploitation

Introduction and Model Much research has been undertaken in order to speed up the processing of semistructured data in general and XML in particular. Many approaches for storage, compression, indexing and querying exist, e.g. [1, 2]. We do not present yet another such algorithm but a unifying model in which these algorithm can be understood. The key idea behind this research is the assumption, that most practical queries are based on a particular pattern of data that can be deduced from the query and which can then be captured using a regular structure amendable to efficient processing techniques. To aid understanding, we divide the problem of query optimisation into five distinct steps, which are presented in Figure 1 and described below: 1. Design of an index for a particular query class: Given a particular query pattern or class, indices can be devised, which support easy evaluation. If the index is covering, we can even dispose of the original data and resolve the query entirel