In environments where the state of the system changes rapidly, such as stock trading, air traffic control, network management, and process control, databases have been proposed as the platform to develop automated control systems. Information in such systems consists of "updates," reporting on the state of the environment and…

Presents the design and implementation of a deductive object-oriented database which is built upon a formally defined data model that uses two languages: an imperative programming language called ROCK (Rule Object Computation Kernel), and a logic language called ROLL (Rule Object Logic Language). (LRW)

Investigates new design options for extended schema versioning support for multitemporal relational databases. Discusses the improved functionalities they may provide. Outlines options and basic motivations for the new design solutions, as well as techniques for the management of proposed schema versioning solutions, includes algorithms and…

Shows how counterfactuals and machine learning methods can be used to guide exploration of large databases that addresses some of the fundamental problems that organizations face in learning from data. Discusses data mining, particularly in the financial arena; generating useful knowledge from data; and the evaluation of counterfactuals. (LRW)

Performance is a critical factor hindering the use of object-oriented databases (OODB). This article proposes a new and uniform indexing scheme for enhancing OODBs with advantages for small range, clustered sets queries. Reviews several other indexing schemes; presents the U-index scheme; discusses its performance; and presents experimental…

Presents an access method for temporal data called the Snapshot Index that reconstructs a past state of a time-evolving collection of objects. Previous approaches to temporal access methods are reviewed, and migrating data to write-once optical disks are discussed. (Author/LRW)

Discussion of local area networks and multiple file servers for concurrent information retrievals provides a rationale for workload and data allocation and presents an analytical model which will attain effective allocation policies. Nonlinear integer programming is discussed, and computational results show the effectiveness of the heuristic.…

Discussion of methodologies for the semantic integration of databases focuses on formalizing the notion of schema equivalence and the schema integration process. Topics include common data model; the Entity-Relationship (ER)model; transformation of ER models; transformational, mapping, and behavioral schema equivalence; and knowledge-based…

Discussion of data repositories available in global information systems focuses on facilitating access by providing semantic views. Highlights include the mapping relation; syntax and semantics of the mapping; query formulation and processing; terminological systems for semantic views; and relational algebraic expressions. (LRW)

Presents an improved inverted region quadtree variation called Dynamic Inverted Quadtree that is able to support and index a pictorial database. Pattern-searching algorithms are described, and the space needs of Fully Inverted and Dynamic Inverted Quadtrees are analytically compared based on a model of image randomness expressed as a branching…

Discusses indexes for text databases and presents an efficient implementation of an index for text searching called PAT array, or suffix array, where the database is stored on secondary storage devices such as magnetic or optical disks. Additional hierarchical index structures and searching algorithms are proposed that improve searching time, and…