3 research outputs found

    Interval-based temporal functional dependencies: specification and verification

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    In the temporal database literature, every fact stored in a database may beequipped with two temporal dimensions: the valid time, which describes the time whenthe fact is true in the modeled reality, and the transaction time, which describes the timewhen the fact is current in the database and can be retrieved. Temporal functional dependencies(TFDs) add valid time to classical functional dependencies (FDs) in order to expressdatabase integrity constraints over the flow of time. Currently, proposals dealing with TFDsadopt a point-based approach, where tuples hold at specific time points, to express integrityconstraints such as \u201cfor each month, the salary of an employee depends only on his role\u201d. Tothe best of our knowledge, there are no proposals dealing with interval-based temporal functionaldependencies (ITFDs), where the associated valid time is represented by an intervaland there is the need of representing both point-based and interval-based data dependencies.In this paper, we propose ITFDs based on Allen\u2019s interval relations and discuss theirexpressive power with respect to other TFDs proposed in the literature: ITFDs allow us toexpress interval-based data dependencies, which cannot be expressed through the existingpoint-based TFDs. ITFDs allow one to express constraints such as \u201cemployees starting towork the same day with the same role get the same salary\u201d or \u201cemployees with a given roleworking on a project cannot start to work with the same role on another project that willend before the first one\u201d. Furthermore, we propose new algorithms based on B-trees to efficientlyverify the satisfaction of ITFDs in a temporal database. These algorithms guaranteethat, starting from a relation satisfying a set of ITFDs, the updated relation still satisfies thegiven ITFDs

    Gerenciamento de restrições de integridade para dados geoespaciais multi-escala

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    Orientador: Claudia Maria Bauzer MedeirosDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de ComputaçãoResumo: Trabalhar em questões relativas a dados geoespaciais presentes em múltiplas escalas apresenta inúmeros desafios que têm sido atacados pelos pesquisadores da área de GIS (Sistemas de Informação Geográfica). De fato, um dado problema do mundo real deve frequentemente ser estudado em escalas distintas para ser resolvido. Outro fator a ser considerado é a possibilidade de manter o histórico de mudanças em cada escala. Além disso, uma das principais metas de ambientes multi-escala _e garantir a manipulação de informações sem qualquer contradição entre suas diferentes representações. A noção de escala extrapola inclusive a questão espacial, pois se aplica também, por exemplo, _a escala temporal. Estes problemas serão analisados nesta dissertação, resultando nas seguintes contribuições: (a) proposta do modelo DBV (Database Version) multi-escala para gerenciar de forma transparente dados de múltiplas escalas sob a perspectiva de bancos de dados; (b) especificação de restrições de integridade multi-escala; (c) implementação de uma plataforma que suporte o modelo e as restrições, testados com dados reais multi-escalaAbstract: Work on multi-scale issues concerning geospatial data presents countless challenges that have been long attacked by GIScience (Geographic Information Science) researchers. Indeed, a given real world problem must often be studied at distinct scales in order to be solved. Another factor to be considered is the possibility of maintaining the history of changes at each scale. Moreover, one of the main goals of multi-scale environments is to guarantee the manipulation of information without any contradiction among the different representations. The concept of scale goes beyond issues of space, since it also applies, for instance, to time. These problems will be analyzed in this thesis, resulting in the following contributions: (a) the proposal of the DBV (Database Version) multi-scale model to handle data at multiple scales from a database perspective; (b) the specification of multi-scale integrity constraints; (c) the implementation of a platform to support model and constraints, tested with real multi-scale dataMestradoCiência da ComputaçãoMestre em Ciência da Computaçã

    Providing Multi-scale Consistency For Multi-scale Geospatial Data

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    We are immersed in a world in which we constantly deal (and cope) with objects and phenomena in a variety of scales in space and time. With the increase in collaborative and interdisciplinary research, there appeared a growing need for handling data in multiple scales and representations, within a single environment. The so called multi-scale environments must guarantee the manipulation of information while ensuring consistency. This paper is concerned with the challenges of managing data in multiple scales, while preserving consistency across scales. Its main contributions are the following: (a) the specification of generic, extensible multiscale integrity constraints; and (b) the implementation of a prototype based on data versioning, which supports the maintenance of these constraints. This prototype was tested using watershed data from Brazil. Copyright © 2013 ACM.Microsoft Research,Tableau Software,Paradigm4,SciDB,Hopkins UniversityAllen, J., Maintaining knowledge about temporal intervals (1983) Commun. ACM, 26 (11), pp. 832-843Bertino, E., Camossi, E., Bertolotto, M., Multi-granular spatio-temporal object models: Concepts and research directions (2010) Object Databases, 5936, pp. 132-148. , Springer Berlin/HeidelbergCamossi, E., Bertino, E., Guerrini, G., Bertolotto, M., Adaptive management of multigranular spatio-temporal object attributes (2009) Advances in Spatial and Temporal Databases, pp. 320-337. , volume 5644 of Lecture Notes in Computer Science, Springer Berlin/HeidelbergCamossi, E., Bertolotto, M., Bertino, E., Multigranular spatio-temporal models: Implementation challenges (2008) Proc. of the 16th ACM SIGSPATIAL, GIS '08, , pages 63:1-63:4. ACMCellary, W., Jomier, G., Consistency of versions in object-oriented databases (1990) Proc. of 16th International Conference on Very Large Databases, pp. 432-441. , Morgan KaufmannCockcroft, S., A taxonomy of spatial data integrity constraints (1997) GeoInformatica, 1 (4), pp. 327-343Cockcroft, S., The design and implementation of a repository for the management of spatial data integrity constraints (2004) GeoInformatica, 8, pp. 49-69Currim, F., Currim, S., Dyreson, C., Snodgrass, R., Thomas, S., Zhang, R., Adding temporal constraints to xml schema (2011) Knowledge and Data Engineering, IEEE Transactions on, p. 1. , PP(99)Currim, F., Ram, S., Modeling spatial and temporal set-based constraints during conceptual database design (2012) Info. Sys. Research, 23 (1), pp. 109-128Delis, V., Hadzilacos, T., On the assessment of generalisation consistency (1997) Advances in Spatial Databases, pp. 321-335. , volume 1262 of Lecture Notes in Computer Science, Springer Berlin/HeidelbergDias, T., Câmara, G., Davis, C., (2005) Geographic Databases, Chapter Spatio-temporal Models, pp. 147-180. , MundoGEODoucet, A., Fauvet, M., Gançarski, S., Jomier, G., Monties, S., Using database versions to implement temporal integrity constraints (1997) CDB, pp. 219-233Doucet, A., Gaņcarski, S., Jomier, G., Monties, S., Integrity constraints in multiversion databases (1996) BNCOD, pp. 56-73Doucet, A., Monties, S., Versions of integrity constraints in multiversion databases (1997) DEXA, pp. 252-261Egenhofer, M., Clementini, E., Di Felice, P., Evaluating inconsistencies among multiple representations (1994) Proc. of the Sixth International Symposium on Spatial Data Handling, 2, pp. 901-920Gubiani, D., Montanari, A., A conceptual spatial model supporting topologically-consistent multiple representations (2008) Proc. of the 16th ACM SIGSPATIAL, GIS '08, , pages 9:1-9:10. ACMGuting, R., An introduction to spatial database systems (1994) The VLDB Journal, 3 (4), pp. 357-400Longo, J., (2013) Management of Integrity Constraints for Multi-scale Geospatial Data, , Master's thesis, University of CampinasLongo, J., Camargo, L., Medeiros, C., Santanchè, A., Using the dbv model to maintain versions of multi-scale geospatial data (2012) Advances in Conceptual Modeling, pp. 284-293. , volume 7518 of Lecture Notes in Computer Science, Springer Berlin HeidelbergMäs, S., Reinhardt, W., Categories of geospatial and temporal integrity constraints (2009) Advanced Geographic Information Systems Web Services, 2009, GEOWS '09, pp. 146-151. , International Conference on, febMäs, S., Wang, F., Reinhardt, W., Using ontologies for integrity constraint definition (2005) Proc. of the 4th International Symposium on Spatial Data Quality, pp. 304-313. , ISSDQMcmaster, R., Shea, K., (1992) Generalization in Digital Cartography, , In Resource Publication of the Association of American GeographersMedeiros, C., Cilia, M., Maintenance of binary topological constraints through active databases (1995) Proceedings of the 3rd ACM Workshop on Advances in GIS, pp. 127-134. , Citeseer, DecemberOpengis Implementation Specification for Geographic Information - Simple Feature Access - Part 1: Common Architecture, , http://www.opengeospatial.org/standards/sfaOMG. Ocl 2.3.1., , http://www.omg.org/spec/OCL/2.3.1Oosterom, P., Research and development in geo-information generalisation and multiple representation (2009) Computers, Environment and Urban Systems, 33 (5), pp. 303-310Pandey, R., Architectural description languages (adls) vs uml: A review (2010) SIGSOFT Softw. Eng. Notes, 35, pp. 1-5Papadias, D., Sellis, T., On the qualitative representation of spatial knowledge in 2d space (1994) VLDB Journal, 3, pp. 479-516Salehi, M., Bédard, Y., Mostafavi, M., Brodeur, J., From transactional spatial databases integrity constraints to spatial datacubes integrity constraints (2007) Proc. of the 5th International Symposium on Spatial Data QualitySalehi, M., Bédard, Y., Mostafavi, M., Brodeur, J., Formal classification of integrity constraints in spatiotemporal database applications (2011) Journal of Visual Languages & Computing, (5), pp. 323-339Sarjakoski, L., Conceptual models of generalisation and multiple representation (2007) Generalisation of Geographic Information, pp. 11-35. , Elsevier Science B.VStoter, J., Visser, T., Van Oosterom, P., Quak, W., Bakker, N., A semantic-rich multi-scale information model for topography (2011) International Journal of Geographical Information Science, 25 (5), pp. 739-763Thalheim, B., Integrity constraints in (conceptual) database models (2011) The Evolution of Conceptual Modeling, pp. 42-67. , volume 6520 of Lecture Notes in Computer Science, Springer Berlin/HeidelbergWang, F., Reinhardt, W., Extending geographic data modeling by adopting constraint decision table to specify spatial integrity constraints (2007) The European Information Society, pp. 435-454. , Lecture Notes in Geoinformation and Cartography, Springer Berlin HeidelbergWebster, M., (1997) Merriam-Webster's Collegiate Dictionary, , 10th edition. Merriam-Webster, In
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