Query Rewriting Algorithm Evaluation for XML Security Views

Abstract. We investigate the experimental effectiveness of query rewriting over XML security views. Our model consists of access control policies specified over DTDs with XPath expression for data-dependent access control policies. We provide the notion of security views for characterizing information accessible to authorized users. This is a transformed (sanitized) DTD schema that is used by users for query formulation. To avoid the overhead of view materialization in query answering, these queries later undergo rewriting so that they are valid over the original DTD schema, and thus the query answer is computed from the original XML data. We provide an algorithm for query rewriting and show its performance compared with the naive approach, i.e. the approach that requires view materialization. Key words: query rewriting, XML views, XPath annotation, algorithm, evaluation, security

• Type: Conference
• Year: 2007
• Where: SDMW
• Authors: Nataliya Rassadko
• Keywords: Access Control Policies, Query Rewriting, SDMW 2007, Security Views