SIGMOD

ACM SIGMOD is pleased to announce a new set of on line services for members, including on line copies of portions of the SIGMOD Record (including all funding columns since 1991, and wider coverage of the Record beginning with this issue), an archive of ...

As a Professor in the Computer Science Department of the Polytechnical Institute of Bucharest, Romania, I would like to bring to your attention the effort of a group of professionals, researchers, students and professors around the world. This effort, ...

This paper describes work carried out on a model for the versioning of class definitions in an object-oriented database. By defining update and backdate functions on attributes of the previous and current version of a class definition, instances of any ...

Workflow management is primarily concerned with dependencies between the tasks of a workflow, to ensure correct control flow and data flow. Transaction management, on the other hand, is concerned with preserving data dependencies by preventing execution ...

Despite the fact that computer memory costs have decreased dramatically over the past few years, data storage still remains, and will probably always remain, an important cost factor for many large scale database applications. Compressing data in a ...

The distributed locking based approaches to concurrency control in a distributed database system, are prone to occurrence of deadlocks. An algorithm for deadlock prevention has been considered in this proposal. In this algorithm, a transaction is ...

This report presents a review of the problems that were discussed during the Workshop on Semantic Heterogeneity and Interoperability in Multidatabase Systems. The workshop participants discussed the importance of interoperation in the U S WEST ...

One of the most important technologies needed across many traditional areas as well as emerging new frontiers of computing, is the management of visual information. For example, most of the Grand Challenge applications, under the High Performance ...

A cornerstone of modern database systems is physical data independence, i.e., the separation of a type and its associated operations from its physical representation in memory and on storage media. Users manipulate and query data at the logical level; ...

The last issue of this column appeared six months ago, so in the interim many requests for proposals have been issued, with many of their due dates already past. We are happy to announce the availability of up-to-the-minute funding information on line, ...