Changes occur very quickly within competitive business environments, and successful companies need to respond quickly by producing and delivering improved products and services, or by changing their business strategies and operational systems. Such changes may require redesign of resources, processes, strategies or organizational structures within the enterprise. Redesign is an expensive and ri...

In this paper we present, by way of case studies, a proof of concept, based on a prototype working on a automotive data set, aimed at showing the potential usefulness of using formulas of Łukasiewicz propositional logic to query databases in a fuzzy way. Our approach distinguishes itself for its stress on the purely linguistic, contraposed with numeric, formulations of queries. Our queries are ...

Non-deterministic extensions are needed in logic-based languages, such as First-Order relational languages and Datalog, to enhance their expressive power and support the eÆcient formulation of low-complexity problems and database queries. In this paper, we study the semantics and expressive power of the various non-deterministic constructs proposed in the past, including various versions of the...

1 I N T R O D U C T I O N Polyinstantiat ion has generated a great deal of controversy lately. Some have argued tha t polyinstantiat ion and integrity are fundamental ly incompatible, and have proposed alternatives to polyinstantiation. Others have argued about the correct definition of polyinstantiat ion and its operational semantics. Much has been writ ten about this topic, as can be seen fro...

Past research concerning information systems (IS) risk has mainly focused on development risk. However, the impact of any risk event that occurs once the system is operational can be far more extensive. Such events are due to what has been termed operational risk. Our research is concerned with operational risk that involves an IS – or IS-related operational risk – which has received little att...

A decision support system with over one billion rows of data has been developed at Lands’ End using the IBM DATABASE 2” (DB2@) relational database management system. This corporate database is a subset of an Information Warehouse” framework and functions as both a decision support system server and an application enabler. The corporate database uses operational data gathered from order processi...

Database design typically results in SQL create table commands and integrity constraints which are specified by foreign-keys, cascading deletes, etc. Specific products of the important database vendors provide a limited form of higher level design of the database relations and their associations. The design is then very close to physical design of the schema which is implemented under the assoc...

One major source of confusion, and consequent c&icisms, about object-oriented databases has been the lack of a comprehensive model of queries. Although there is a reasonable degree of agreement about an object-oriented data model, few operational systems support a query model for object-oriented databases. In this paper, we present a rather comprehensive query model which is consistent with obj...

A runtime approach to model-generic schema and data translation is proposed. It is based on our previous work on MIDST, a platform conceived to perform translations in an off-line fashion. In the original approach, the source database is imported into MIDST dictionary, where it is stored according to a universal model. Then the translation is applied within the tool as a composition of elementa...

A data warehouse is an integrated and time-varying collection of data derived from operational data and primarily used in strategic decision making by means of OLAP techniques. Although it is generally agreed that warehouse design is a non-trivial problem and that multidimensional data models and star or snowflake schemata are relevant in this context, there exist neither methods for deriving s...