The efficient execution of integration processes between distributed, heterogeneous data sources and applications is a challenging research area of data management. These integration processes are an abstraction for workflow-based integration tasks, ...

The skyline query, as an important operator in databases for multi-preference analysis and decision making, has received much attention recently due to its wide application backgrounds. In this paper, we consider the skyline query problem in Wireless ...

The streaming evaluation is a popular way of evaluating queries on XML documents. Besides its many advantages, it is also the only option for a number of important XML applications. Unfortunately, existing algorithms focus almost exclusively on tree-...

Structured P2P overlays supporting standard database functionalities are a popular choice for building large-scale distributed data management systems. In such systems, estimating the number of answers for structured queries can help approximating query ...

The problem of decentralized data sharing is relevant for a wide range of applications and is still a source of major theoretical and practical challenges, in spite of many years of sustained research in information integration. We focus on the ...

Range queries for querying the current and future positions of the moving objects have received growing interests in the research community. Existing methods, however, assume that an object only moves along an anticipated path. In this paper, we study ...

Traditional workload management methods mainly focus on the current system status while information about the interaction between queued and running transactions is largely ignored. An exception to this is the transaction reordering method, which ...

In a number of application areas, distributed database systems can be used to provide persistent storage of data while providing efficient access for both local and remote data. With an increasing number of sites (computers) involved in a query, the ...

In database outsourcing, an enterprise contracts its database management tasks to an outside database service provider to eliminate in-house hardware, software, and expertise needs for running DBMSs. This is attractive especially for the parties with ...

Inverted indexes have become the standard indexing method for supporting search queries in a variety of content-based applications. Examples of such applications include enterprise document management, e-mail, web search, and social networks. One ...

We propose a new method to build persistent suffix trees for indexing the genomic data. Our algorithm DiGeST (Disk-Based Genomic Suffix Tree) improves significantly over previous work in reducing the random access to the input string and performing only ...

Efficiency of memory-intensive operations is a key factor in obtaining good performance during multi-join query processing. The pipelined execution of these queries forces the operations in the query plan to be processed concurrently. Making a wrong ...

Query processing techniques for XML data have focused mainly on tree-pattern queries (TPQs). However, the need for querying XML data sources whose structure is very complex or not fully known to the user, and the need to integrate multiple XML data ...

IBM� DB2� 9 is a truly hybrid commercial database system that combines XML and relational data. It provides native support for XML storage and indexing, and query evaluation support for XQuery. By building a hybrid system, the designers of DB2 9 were ...

The typical workload in a database system consists of a mixture of multiple queries of different types, running concurrently and interacting with each other. Hence, optimizing performance requires reasoning about query mixes and their interactions, ...

Schema mapping plays a fundamental role in modern information systems. Mapping composition is an operator that combines a chain of successive schema mappings into a single schema mapping. By pre-computing the composed schema mapping, the system can ...

Real-time materialized view maintenance has become increasingly popular, especially in real-time data warehousing and data streaming environments. Upon updates to base relations, maintaining the corresponding materialized views can bring a heavy burden ...

The emergence of numerous data sources online has presented a pressing need for more automatic yet accurate data integration techniques. For the data returned from querying such sources, most works focus on how to extract the embedded structured data ...

In this paper, we propose minimum-effort driven navigational techniques for enterprise database systems based on the faceted search paradigm. Our proposed techniques dynamically suggest facets for drilling down into the database such that the cost of ...