220 research outputs found
A Review of integrity constraint maintenance and view updating techniques
Two interrelated problems may arise when updating a database. On one
hand, when an update is applied to the database, integrity constraints
may become violated. In such case, the integrity constraint maintenance
approach tries to obtain additional updates to keep integrity
constraints satisfied. On the other hand, when updates of derived or
view facts are requested, a view updating mechanism must be applied to
translate the update request into correct updates of the underlying base
facts.
This survey reviews the research performed on integrity constraint
maintenance and view updating. It is proposed a general framework to
classify and to compare methods that tackle integrity constraint
maintenance and/or view updating. Then, we analyze some of these methods
in more detail to identify their actual contribution and the main
limitations they may present.Postprint (published version
Structuring the process of integrity maintenance (extended version)
Two different approaches have been traditionally considered for dealing with the process of integrity constraints
enforcement: integrity checking and integrity maintenance. However, while previous research in the first approach has
mainly addressed efficiency issues, research in the second approach has been mainly concentrated in being able to
generate all possible repairs that falsify an integrity constraint violation. In this paper we address efficiency issues during
the process of integrity maintenance. In this sense, we propose a technique which improves efficiency of existing methods
by defining the order in which maintenance of integrity constraints should be performed. Moreover, we use also this
technique for being able to handle in an integrated way the integrity constraintsPostprint (published version
Simplification of UML/OCL schemas for efficient reasoning
Ensuring the correctness of a conceptual schema is an essential task in order to avoid the propagation of errors during software development. The kind of reasoning required to perform such task is known to be exponential for UML class diagrams alone and even harder when considering OCL constraints. Motivated by this issue, we propose an innovative method aimed at removing constraints and other UML elements of the schema to obtain a simplified one that preserve the same reasoning outcomes. In this way, we can reason about the correctness of the initial artifact by reasoning on a simplified version of it. Thus, the efficiency of the reasoning process is significantly improved. In addition, since our method is independent from the reasoning engine used, any reasoning method may benefit from it.Peer ReviewedPostprint (author's final draft
On the practical applicability of current techniques for reasoning on the structural schema
There has been plenty of promising results for providing automated reasoning on the structural part of the conceptual schema and several prototype tools have been developed with this purpose. However, most of these results have remained at the academical level and the
industry is not aware of them or it does not consider them relevant enough since it is not using them in software development. With the aim of reducing the gap between academy and industry, the discussion of the participants in this group was aimed at providing an
answer to the following questions:
1. What do we need to convince the industry that this technology is useful?
2. Can we come up with a common vocabulary for the various research disciplines that work on this topic?
3. Can we come up with a research agenda of the problems we have to solve?Postprint (published version
Transformation Techniques for OCL Constraints
Constraints play a key role in the definition of conceptual schemas. In the UML, constraints are usually specified by means of invariants written in the OCL. However, due to the high expressiveness of the OCL, the designer has different syntactic alternatives to express each constraint. The techniques presented in this paper assist the designer during the definition of the constraints by means of generating equivalent alternatives for the initially defined ones. Moreover, in the context of the MDA, transformations between these different alternatives are required as part of the PIM-to-PIM, PIM-to-PSM or PIM-to-code transformations of the original conceptual schema
IoT semantic data Integration through ontologies
In this position statement we advocate how the use of ontologies may provide a proper solution for IoT semantic data integration. With this, we will improve IoT interoperability and will facilitate the development of software applications that allow providing management and monitoring of different IoT installations in a generic and homogeneous way.This work is partially funded by: Industrial Doctorates DI-2019 from Generalitat de Catalunya, project TIN2017-87610- R from MCIN/AEI/10.13039/501100011033, FEDER “Una manera de hacer Europa”, and project 2017-SGR-1749 from Generalitat de Catalunya. Also with the support of inLab FIB at UPC and Worldsensing.Peer ReviewedPostprint (author's final draft
The Constructive method for query containment checking (extended version)
We present a new method that checks Query Containment for queries with negated derived atoms and/or integrity constraints.
Existing methods for Query Containment checking that deal with these cases do not check actually containment but another
related property called uniform containment, which is a sufficient but not necessary condition for containment. Our method can
be seen as an extension of the canonical databases approach beyond the class of conjunctive queries.Postprint (published version
El Mètode dels esdeveniments per a l'Actualització de vistes en bases de dades deductives
En esta tesis se presenta un nuevo método, llamado método de los eventos, para la actualización de vistas en bases de datos deductivas. Este método aumenta la base de datos con un conjunto de reglas, llamadas reglas de transición y de evento, que definen explícitamente las inserciones y las supresiones inducidas por una modificación de la base de datos. Mediante estas reglas, se utiliza la resolución SIDNF para obtener todas las traducciones mínimas que satisfacen una petición de actualización de vista.Una de las contribuciones principales de esta tesis es la demostración del hecho que el método de los eventos es completo en bases de datos estratificados. Es decir, en este tipo de bases de datos dicho método obtiene todas las traducciones validas. Otras ventajas importantes del método son la incorporación de la comprobación de integridad en el proceso de traducción, el tratamiento uniforme de inserciones y supresiones, la posibilidad de prevenir efectos laterales y la traducción de peticiones de modificación de vista.Por todas estas razones, se puede decir que el método de los eventos tiene todo el poder de los métodos propuestos hasta el momento actual para la utilización de vistas en bases de datos deductivas, pero sin presentar algunas de sus limitaciones
Kopernik : modeling business processes for digital customers
This paper presents the Kopernik methodology for modeling business processes for digital customers. These processes require a high degree of flexibility in the execution of their tasks or actions. We achieve this by using the artifact-centric approach to process modeling and the use of condition-action rules. The processes modeled following Kopernik can then be implemented in an existing commercial tool, Balandra.Preprin
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