PATAXÓ: A Framework to Allow Updates Through XML Views

XML has become an important medium for data exchange, and is frequently used as an interface to (i.e., a view of) a relational database. Although a lot of work has been done on querying relational databases through XML views, the problem of updating relational databases through XML views has not received much attention. In this work, we map XML views expressed using a subset of XQuery to a corresponding set of relational views. Thus, we transform the problem of updating relational databases through XML views into a classical problem of updating relational databases through relational views. We then show how updates on the XML view are mapped to updates on the corresponding relational views. Existing work on updating relational views can then be leveraged to determine whether or not the relational views are updatable with respect to the relational updates, and if so, to translate the updates to the underlying relational database

Updating XML Views

Update operations over XML views are essential for applications using XML views. In this dissertation work, we provide scalable solutions to support updating through XML views defined over relational databases. Especially we focus on the update-public semantic, where updates are always public (made to the public database), and the update-local semantic, where update effects are first kept local and then made public as and when required. Towards this, we propose the clean extended-source theory for determining whether a correct view update translation exists, which then serves as a theoretical foundation for us to design practical XML view updating algorithms. Under update-public semantic, state-of-the-art view updating work focus on identifying the correct update translation purely on the data. We instead take a schema-centric solution, which utilizes the schema of the underlying source to effectively prune updates that are guaranteed to be not translatable and pass updates that are guaranteed to be translatable directly to the SQL engine. Only those updates that could not be classified using schema knowledge are finally analyzed by examining the data. This required data-level check is further optimized under schema guidance to prune the search space for finding a correct translation. As the first work addressing the update-local semantic, we propose a practical framework, called LoGo. LoGo Localizes the view update translation, while preserves the properties of views being side-effect free and updates being always updatable. LoGo also supports on-demand merging of the local database of the subject viewinto the public database (also called global database), while still guaranteeing the subject view being free of side effects. A flexible synchronization service is provided in LoGo that enables all other views defined over the same public database to be refreshed, i.e., synchronized with the publically committed changes, if so desired. Further, given that XMLis an ordered datamodel,we propose an ordersensitive solution named O-HUX to support XML view updating with order. We have implemented the algorithms, along with respective optimization techniques. Experimental results confirm the effectiveness of the proposed services, and highlight its performance characteristics

Optimizing View Queries in ROLEX to Support Navigable Result Trees

An increasing number of applications use XML data published from relational databases. For speed and convenience, such applications routinely cache this XML data locally and access it through standard navigational interfaces such as DOM, sacrificing the consistency and integrity guarantees provided by a DBMS for speed. The ROLEX system is being built to extend the capabilities of relational database systems to deliver fast, consistent and navigable XML views of relational data to an application via a virtual DOM interface

Automatic Physical Design for XML Databases

Database systems employ physical structures such as indexes and materialized views to improve query performance, potentially by orders of magnitude. It is therefore important for a database administrator to choose the appropriate configuration of these physical structures (i.e., the appropriate physical design) for a given database. Deciding on the physical design of a database is not an easy task, and a considerable amount of research exists on automatic physical design tools for relational databases. Recently, XML database systems are increasingly being used for managing highly structured XML data, and support for XML data is being added to commercial relational database systems. This raises the important question of how to choose the appropriate physical design (i.e., the appropriate set of physical structures) for an XML database. Relational automatic physical design tools are not adequate, so new research is needed in this area. In this thesis, we address the problem of automatic physical design for XML databases, which is the process of automatically selecting the best set of physical structures for a given database and a given query workload representing the client application's usage patterns of this data. We focus on recommending two types of physical structures: XML indexes and relational materialized views of XML data. For each of these structures, we study the recommendation process and present a design advisor that automatically recommends a configuration of physical structures given an XML database and a workload of XML queries. The recommendation process is divided into four main phases: (1) enumerating candidate physical structures, (2) generalizing candidate structures in order to generate more candidates that are useful to queries that are not seen in the given workload but similar to the workload queries, (3) estimating the benefit of various candidate structures, and (4) selecting the best set of candidate structures for the given database and workload. We present a design advisor for recommending XML indexes, one for recommending materialized views, and an integrated design advisor that recommends both indexes and materialized views. A key characteristic of our advisors is that they are tightly coupled with the query optimizer of the database system, and rely on the optimizer for enumerating and evaluating physical designs whenever possible. This characteristic makes our techniques suitable for any database system that complies with a set of minimum requirements listed within the thesis. We have implemented the index, materialized view, and integrated advisors in a prototype version of IBM DB2 V9, which supports both relational and XML data, and we experimentally demonstrate the effectiveness of their recommendations using this implementation

Efficient processing of XML documents

Ph.DDOCTOR OF PHILOSOPH

Designing and querying XML views based on the ORA-SS data model

Ph.DDOCTOR OF PHILOSOPH

Proceedings of The Multi-Agent Logics, Languages, and Organisations Federated Workshops (MALLOW 2010)

http://ceur-ws.org/Vol-627/allproceedings.pdfInternational audienceMALLOW-2010 is a third edition of a series initiated in 2007 in Durham, and pursued in 2009 in Turin. The objective, as initially stated, is to "provide a venue where: the cost of participation was minimum; participants were able to attend various workshops, so fostering collaboration and cross-fertilization; there was a friendly atmosphere and plenty of time for networking, by maximizing the time participants spent together"

Public Law and Economics

This comprehensive textbook applies economic analysis to public law. The economic analysis of law has revolutionized legal scholarship and teaching in the last half-century, but it has focused mostly on private law, business law, and criminal law. This book extends the analysis to fundamental topics in public law, such as the separation of government powers, regulation by agencies, constitutional rights, and elections. Every public law involves six fundamental processes of government: bargaining, voting, entrenching, delegating, adjudicating, and enforcing. The book devotes two chapters to each process, beginning with the economic theory and then applying the theory to a wide range of puzzles and problems in law. Each chapter concentrates on cases and legal doctrine, showing the relevance of economics to the work of lawyers and judges. Featuring lucid, accessible writing and engaging examples, the book addresses enduring topics in public law as well as modern controversies, including gerrymandering, voter identification laws, and qualified immunity for police

Public Law and Economics

This comprehensive textbook applies economic analysis to public law. The economic analysis of law has revolutionized legal scholarship and teaching in the last half-century, but it has focused mostly on private law, business law, and criminal law. This book extends the analysis to fundamental topics in public law, such as the separation of government powers, regulation by agencies, constitutional rights, and elections. Every public law involves six fundamental processes of government: bargaining, voting, entrenching, delegating, adjudicating, and enforcing. The book devotes two chapters to each process, beginning with the economic theory and then applying the theory to a wide range of puzzles and problems in law. Each chapter concentrates on cases and legal doctrine, showing the relevance of economics to the work of lawyers and judges. Featuring lucid, accessible writing and engaging examples, the book addresses enduring topics in public law as well as modern controversies, including gerrymandering, voter identification laws, and qualified immunity for police