2984369
BigSur: A System For the Management of Earth Science Data
In this paper we present a prototype system for the management of earth science data which is novel in that it takes a DBMS centric view of the the task. Our prototype -called "BigSur" -is shown in the context of its use by two geographically distributed scientific groups with demanding data storage and processing requirements. BigSur currently stores 1 Terabyte of data, about one thousandth of the volume EOSDIS must store. We claim that the design principles embodied in BigSur provide sufficient flexibility to achieve the difficult scientific and technical objectives of Mission to Planet Earth.
12789110
Interoperability, Distributed Applications and Distributed Databases: The Virtual Table Interface
Users of distributed databases and of distributed application frameworks require interoperation of heterogeneous data and components, respectively. In this paper, we examine how an extensible, objectrelational database system can integrate both modes of interoperability. We describe the Virtual Table Interface, a facility of the INFORMIX-Dynamic Server Universal Data Option, that provides simplified access to heterogeneous components and discuss the benefits of integrating data with application components.
5352012
Toward Automated Large-Scale Information Integration and Discovery
The high cost of data consolidation is the key market inhibitor to the adoption of traditional information integration and data warehousing solutions. In this paper, we outline a next-generation integrated database management system that takes traditional information integration, content management, and data warehouse techniques to the next level: the system will be able to integrate a very large number of information sources and automatically construct a global business view in terms of “Universal Business Objects”. We describe techniques for discovering, unifying, and aggregating data from a large number of disparate data sources. Enabling technologies for our solution are XML, web services, caching, messaging, and portals for real-time dashboarding and reporting.
16124888
GORDIAN: efficient and scalable discovery of composite keys
Identification of (composite) key attributes is of fundamental importance for many different data management tasks such as data modeling, data integration, anomaly detection, query formulation, query optimization, and indexing. However, information about keys is often missing or incomplete in many real-world database scenarios. Surprisingly, the fundamental problem of automatic key discovery has received little attention in the existing literature. Existing solutions ignore composite keys, due to the complexity associated with their discovery. Even for simple keys, current algorithms take a brute-force approach; the resulting exponential CPU and memory requirements limit the applicability of these methods to small datasets. In this paper, we describe GORDIAN, a scalable algorithm for automatic discovery of keys in large datasets, including composite keys. GORDIAN can provide exact results very efficiently for both real-world and synthetic datasets. GORDIAN can be used to find (composite) key attributes in any collection of entities, e.g., key column-groups in relational data, or key leaf-node sets in a collection of XML documents with a common schema. We show empirically that GORDIAN can be combined with sampling to efficiently obtain high quality sets of approximate keys even in very large datasets.
30490732
Reality versus imagination
8309392
The ethics and aesthetics of the image interface
Now that we have developed and are introducing media-rich computer human interfaces, it is important to develop a taxonomy that can help us appreciate the power and value of computer systems in order to better quantify them and assess their creative and ethical impact. To date the application of semiosis has been to natural languages and human-human communications. The author suggests that this can now be applied to artificial languages and in particular, their use in human computer interactions, imaging and visualization. The semiology of Charles Sanders Peirce can be applied to this field and may be used to assess the aesthetic (creative) and ethical implications of computer human interface (CHI), imaging and visualization technology and the way it is being developed and used.
739681
BHUNT: Automatic Discovery of Fuzzy Algebraic Constraints in Relational Data
We present the BHUNT scheme for automatically discovering algebraic constraints between pairs of columns in relational data. The constraints may be "fuzzy" in that they hold for most, but not all, of the records, and the columns may be in the same table or different tables. Such constraints are of interest in the context of both data mining and query optimization, and the BHUNT methodology can potentially be adapted to discover fuzzy functional dependencies and other useful relationships. BHUNT first identifies candidate sets of column value pairs that are likely to satisfy an algebraic constraint. This discovery process exploits both system catalog information and data samples, and employs pruning heuristics to control processing costs. For each candidate, BHUNT constructs algebraic constraints by applying statistical histogramming, segmentation, or clustering techniques to samples of column values. Using results from the theory of tolerance intervals, the sample sizes can be chosen to control the number of "exception" records that fail to satisfy the discovered constraints. In query-optimization mode, BHUNT can automatically partition the data into normal and exception records. During subsequent query processing, queries can be modified to incorporate the constraints; the optimizer uses the constraints to identify new, more efficient access paths. The results are then combined with the results of executing the original query against the (small) set of exception records. Experiments on a very large database using a prototype implementation of BHUNT show reductions in table accesses of up to two orders of magnitude, leading to speedups in query processing by up to a factor of 6.8.