CSTL: A Conceptual Schema Testing Language

Like any software artifact, conceptual schemas of information systems can be tested. Testing conceptual schemas has some similarities with testing programs, but there are important differences. We present a list of six kinds of tests that can be applied to conceptual schemas. Some of them require schemas comprising both the structural and the behavioral parts, but we show that it is useful to test incomplete schema fragments, even if they consist of only a few entity and relationship types, integrity constraints and derivation rules. We present CSTL, a language for writing automated tests of executable schemas written in UML/OCL. CSTL follows the style of the modern xUnit testing frameworks. Tests written in CSTL can be executed as many times as needed. We describe an implementation of a test processor, which includes a test manager and a test interpreter that coordinates the execution of the tests. Finally, we apply CSTL to the conceptual schema of a real-world information system

On the meanings of subsetting, specialization and redefinition in UML

UML 2 has improved the expressiveness of the language with respect to associations in several manners. A significant one has been the introduction of the association redefinition concept. Association subsetting and association specialization have been included in UML since its earliest versions and share some relevant features with association redefinition. These similarities among the three constructs make it frequently difficult, especially to novice users, to: decide which one of these concepts is the best suited to model a particular situation; systematically justify their modelling choices. In this report, we present a preliminary empirical investigation on these constructs using as a benchmark a catalogue of model examples produced by different authors which can be considered experts in the conceptual modelling field.Preprin

Reification and Truthmaking Patterns

Reification is a standard technique in conceptual modeling, which consists of including in the domain of discourse entities that may otherwise be hidden or implicit. However, deciding what should be rei- fied is not always easy. Recent work on formal ontology offers us a simple answer: put in the domain of discourse those entities that are responsible for the (alleged) truth of our propositions. These are called truthmakers. Re-visiting previous work, we propose in this paper a systematic analysis of truthmaking patterns for properties and relations based on the ontolog- ical nature of their truthmakers. Truthmaking patterns will be presented as generalization of reification patterns, accounting for the fact that, in some cases, we do not reify a property or a relationship directly, but we rather reify its truthmakers

Conceptual fit: A criterion for COTS selection

COTS systems selection consists in evaluating the user requirements with respect to characteristics of candidate systems, using a set of criteria. One criterion that has received little attention is what we call conceptual fit. The criterion assesses the fit between the conceptual structure of the user requirements and that of a system. We evaluate the fit in terms of the existing misfits. We formally define the notion of conceptual misfit and we present a method that determines the conceptual misfits between the user requirements and a set of candidate systems. The method consists in defining a superschema, the mapping of the conceptual schemas of the candidate systems and of the user requirements to that superschema, and the automatic computation of the existing conceptual misfits. The method has been formalized in UML/OCL. We have conducted an exploratory experiment with the aim of evaluating the feasibility, difficulty and usefulness of the method, with positive results. We believe that the conceptual fit criterion could be taken into account by almost all existing COTS selection methods.Preprin

Asynchronous data retrieval from an object-oriented database

We present an object-oriented semantic database model which, similar to other object-oriented systems, combines the virtues of four concepts: the functional data model, a property inheritance hierarchy, abstract data types and message-driven computation. The main emphasis is on the last of these four concepts. We describe generic procedures that permit queries to be processed in a purely message-driven manner. A database is represented as a network of nodes and directed arcs, in which each node is a logical processing element, capable of communicating with other nodes by exchanging messages. This eliminates the need for shared memory and for centralized control during query processing. Hence, the model is suitable for implementation on a multiprocessor computer architecture, consisting of large numbers of loosely coupled processing elements

A Call to Arms: Revisiting Database Design

Good database design is crucial to obtain a sound, consistent database, and - in turn - good database design methodologies are the best way to achieve the right design. These methodologies are taught to most Computer Science undergraduates, as part of any Introduction to Database class. They can be considered part of the "canon", and indeed, the overall approach to database design has been unchanged for years. Moreover, none of the major database research assessments identify database design as a strategic research direction. Should we conclude that database design is a solved problem? Our thesis is that database design remains a critical unsolved problem. Hence, it should be the subject of more research. Our starting point is the observation that traditional database design is not used in practice - and if it were used it would result in designs that are not well adapted to current environments. In short, database design has failed to keep up with the times. In this paper, we put forth arguments to support our viewpoint, analyze the root causes of this situation and suggest some avenues of research.Comment: Removed spurious column break. Nothing else was change

An Empirical Study on Socio-technical Modeling for Interdisciplinary Privacy Requirements

peer reviewedData protection regulations impose requirements on organizations that require interdisciplinary. Conceptual modeling of information systems, particularly goal modeling, has served to communicate with stakeholders of different backgrounds for software requirements analysis. An extension for a Socio-Technical Security (STS) modeling language was proposed to include data protection modeling concepts to help represent relevant issues of the European Union’s General Data Protection Regulation. This article examines whether models designed with this extension serve as communication facilitators for privacy compliance and common ground across stakeholders. Through a series of 8 focus groups, with 21 subjects, we observed if professionals with different backgrounds (software developers, business analysts, and privacy experts) could detect discuss about the GDPR principles and identify privacy compliance “red flags” that we seeded in a use case. Using a qualitative approach to analyze the data, all the groups discussed the majority of the GDPR principles and identified more than 80% of the seeded red flags, with privacy experts identifying the most. This research provides preliminary results on using conceptual modeling as a communicator facilitator between stakeholders to contribute to a common ground between them

Set-related restrictions for semantic groupings

Semantic database models utilize several fundamental forms of groupings to increase their expressive power. In this paper we consider four of the most common of these constructs; basic set groupings, is-a related groupings, power set groupings, and Cartesian aggregation groupings. For each, we define a number of useful restrictions that control its structure and composition. This permits each grouping to capture more subtle distinctions of the concepts or situations in the application environment. The resulting set of restrictions forms a framework which increases the expressive power of semantic models and specifies various set-related integrity constraints