Data heterogeneity in XML repositories can be tackled by giving users the possibility to obtain approximate answers to their queries. In this setting, several approaches for XPath queries have been defined in the literature. In particular, fuzzy XPath queries have been recently introduced as a formalism to provide users with a clear Understanding of the approximations that the query evaluation process introduces in the answers. However, in many cases, users are not a-priori aware of the maximum approximation degree they Would allow in the answers; rather, they are interested in obtaining the first k answers ranked according to their approximation degrees. In this paper we investigate the problem of top-k fuzzy XPath querying, propose a query language and its associated semantics, and discuss query evaluation.
Top-k Answers to Fuzzy XPath Queries
Fazzinga Bettina;
2009
Abstract
Data heterogeneity in XML repositories can be tackled by giving users the possibility to obtain approximate answers to their queries. In this setting, several approaches for XPath queries have been defined in the literature. In particular, fuzzy XPath queries have been recently introduced as a formalism to provide users with a clear Understanding of the approximations that the query evaluation process introduces in the answers. However, in many cases, users are not a-priori aware of the maximum approximation degree they Would allow in the answers; rather, they are interested in obtaining the first k answers ranked according to their approximation degrees. In this paper we investigate the problem of top-k fuzzy XPath querying, propose a query language and its associated semantics, and discuss query evaluation.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.


