Database Systems (TODS)


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ACM Transactions on Database Systems (TODS), Volume 39 Issue 3, September 2014

Christian S. Jensen
Article No.: 18
DOI: 10.1145/2662448

Towards a Painless Index for Spatial Objects
Rui Zhang, Jianzhong Qi, Martin Stradling, Jin Huang
Article No.: 19
DOI: 10.1145/2629333

Conventional spatial indexes, represented by the R-tree, employ multidimensional tree structures that are complicated and require enormous efforts to implement in a full-fledged database management system (DBMS). An alternative approach for...

Finding Robust Itemsets under Subsampling
Nikolaj Tatti, Fabian Moerchen, Toon Calders
Article No.: 20
DOI: 10.1145/2656261

Mining frequent patterns is plagued by the problem of pattern explosion, making pattern reduction techniques a key challenge in pattern mining. In this article we propose a novel theoretical framework for pattern reduction by measuring the...

Maximizing Range Sum in External Memory
Dong-Wan Choi, Chin-Wan Chung, Yufei Tao
Article No.: 21
DOI: 10.1145/2629477

This article studies the MaxRS problem in spatial databases. Given a set O of weighted points and a rectangle r of a given size, the goal of the MaxRS problem is to find a location of r such that the sum of the weights...

Private Analysis of Graph Structure
Vishesh Karwa, Sofya Raskhodnikova, Adam Smith, Grigory Yaroslavtsev
Article No.: 22
DOI: 10.1145/2611523

We present efficient algorithms for releasing useful statistics about graph data while providing rigorous privacy guarantees. Our algorithms work on datasets that consist of relationships between individuals, such as social ties or email...

Privacy-Preserving Ad-Hoc Equi-Join on Outsourced Data
Hweehwa Pang, Xuhua Ding
Article No.: 23
DOI: 10.1145/2629501

In IT outsourcing, a user may delegate the data storage and query processing functions to a third-party server that is not completely trusted. This gives rise to the need to safeguard the privacy of the database as well as the user queries over...

A Join-Like Operator to Combine Data Cubes and Answer Queries from Multiple Data Cubes
Francesco M. Malvestuto
Article No.: 24
DOI: 10.1145/2638545

In order to answer a “joint” query from multiple data cubes, Pourabass and Shoshani [2007] distinguish the data cube on the measure of interest (called the “primary” data cube) from the other data cubes (called...

Query Rewriting and Optimization for Ontological Databases
Georg Gottlob, Giorgio Orsi, Andreas Pieris
Article No.: 25
DOI: 10.1145/2638546

Ontological queries are evaluated against a knowledge base consisting of an extensional database and an ontology (i.e., a set of logical assertions and constraints that derive new intensional knowledge from the extensional database), rather than...