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In this article, we present the design and implementation of SISYPHUS, a storage manager for data cubes that provides an efficient physical base for performing on-line analytical processing (OLAP) operations. OLAP poses new requirements to the physical storage layer of a database management system. Special characteristics of OLAP cubes such as multidimensionality, hierarchical structure of dimensions, data sparseness, etc., are difficult to handle with ordinary record-oriented storage managers. The SISYPHUS storage manager is based on a chunk-based data model that enables the hierarchical clustering of data with a very low storage cost. In this article we present the implementation of SISYPHUS’ chunk-oriented file system as well as present the core architecture of the system and reason on various design choices and implementation solutions. [Copyright &y& Elsevier]

Presents analytical models that estimate the cost in terms of node and disk access of selection and join queries using R-tree-based structures. Importance of access methods and spatial query cost models for spatial query processing and estimation; Use of selection and join queries as fundamental operations in Data Base Management Systems.

In this paper we study database query languages and their use for programming nontraditional applications, such as engineering and artificial intelligence applications. In such environments, database programs are used to code applications that work over large data sets it- siding in databases. Optimizing such programs then becomes a necessity. We look at various optimization techniques and suggest transformations to be used for Improving the performance of database programs. These transformations result in new equivalent database programs with better space and lime performance. Several of these techniques apply to classical query languages, although the primary focus of this paper is on extended query languages which include an iteration operator. [ABSTRACT FROM AUTHOR]

Extraction-Transformation-Loading (ETL) tools are pieces of software responsible for the extraction of data from several sources, their cleansing, customization, and insertion into a data warehouse. In this paper, we delve into the logical optimization of ETL processes, modeling it as a state-space search problem. We consider each ETL workflow as a state and fabricate the state space through a set of correct state transitions. Moreover, we provide an exhaustive and two heuristic algorithms toward the minimization of the execution cost of an ETL workflow. The heuristic algorithm with greedy characteristics significantly outperforms the other two algorithms for a large set of experimental cases. [ABSTRACT FROM AUTHOR]

Commercially available database systems do not meet the information and processing needs of design and manufacturing environments. A new generation of systems-engineering Information systems-must be built to meet these needs. In this paper, we address the architectural and computational aspects of such systems and propose solutions. We argue that a mainframe-workstation architecture is needed to provide distributed functionality while ensuring high availability and low communication overhead, that explicit control of meta-knowledge is needed to support extendibility and evolution, that large rule bases are needed to make the knowledge of the systems active, and that incremental computation models are needed to achieve the required performance of such engineering information systems. [ABSTRACT FROM AUTHOR]

Pictorial databases require efficient and direct spatial search based on the analog form of spatial objects and relationships instead of search based on some cumbersome alphanumeric encodings of the pictures. This paper briefly describes PSQL, a query language which allows pictorial domains to be presented to the user in their analog form and allows him to do direct manipulation on the objects found on those domains. Direct spatial search and computation on the pictures is done using efficient data structures, R- and R+-trees (multi-dimensional B-trees), which are excellent devices for searching spatial objects and relationships found on pictures. [ABSTRACT FROM AUTHOR]