Database Systems (TODS)


Search Issue
enter search term and/or author name


ACM Transactions on Database Systems (TODS), Volume 35 Issue 1, February 2010

Supporting views in data stream management systems
Thanaa M. Ghanem, Ahmed K. Elmagarmid, Per-Åke Larson, Walid G. Aref
Article No.: 1
DOI: 10.1145/1670243.1670244

In relational database management systems, views supplement basic query constructs to cope with the demand for “higher-level” views of data. Moreover, in traditional query optimization, answering a query using a set of existing...

Analyses of multi-level and multi-component compressed bitmap indexes
Kesheng Wu, Arie Shoshani, Kurt Stockinger
Article No.: 2
DOI: 10.1145/1670243.1670245

Bitmap indexes are known as the most effective indexing methods for range queries on append-only data, and many different bitmap indexes have been proposed in the research literature. However, only two of the simplest ones are used in commercial...

Reverse skyline search in uncertain databases
Xiang Lian, Lei Chen
Article No.: 3
DOI: 10.1145/1670243.1670246

Reverse skyline queries over uncertain databases have many important applications such as sensor data monitoring and business planning. Due to the wide existence of uncertainty in many real-world data, answering reverse skyline queries accurately...

The pq-gram distance between ordered labeled trees
Nikolaus Augsten, Michael Böhlen, Johann Gamper
Article No.: 4
DOI: 10.1145/1670243.1670247

When integrating data from autonomous sources, exact matches of data items that represent the same real-world object often fail due to a lack of common keys. Yet in many cases structural information is available and can be used to match such data....

An information-theoretic analysis of worst-case redundancy in database design
Solmaz Kolahi, Leonid Libkin
Article No.: 5
DOI: 10.1145/1670243.1670248

Normal forms that guide the process of database schema design have several key goals such as elimination of redundancies and preservation of integrity constraints, such as functional dependencies. It has long been known that complete elimination...

Optimal algorithms for evaluating rank joins in database systems
Karl Schnaitter, Neoklis Polyzotis
Article No.: 6
DOI: 10.1145/1670243.1670249

In the rank join problem, we are given a set of relations and a scoring function, and the goal is to return the join results with the top k scores. It is often the case in practice that the inputs may be accessed in ranked order and the...

Automatic virtual machine configuration for database workloads
Ahmed A. Soror, Umar Farooq Minhas, Ashraf Aboulnaga, Kenneth Salem, Peter Kokosielis, Sunil Kamath
Article No.: 7
DOI: 10.1145/1670243.1670250

Virtual machine monitors are becoming popular tools for the deployment of database management systems and other enterprise software. In this article, we consider a common resource consolidation scenario in which several database management system...