Exploració per autor "Rull, Guillem"

Ara es mostren els items 1-9 de 9

    • Computing explanations for unlively queries in databases 

      Rull, Guillem; Farré Tost, Carles; Teniente López, Ernest; Urpí Tubella, Antoni (2007-06)
      Report de recerca
      Accés obert
      A query is lively in a database schema if it returns a non-empty answer for some database satisfying the schema. Debugging a database schema requires not only determining queries (as well as views or tables) that are not ...

    • Contención de consultas con valores nulos usando el método CQC 

      Rull, Guillem; Farré Tost, Carles; Urpí Tubella, Antoni (International Centre for Numerical Methods in Engineering (CIMNE), 2006)
      Text en actes de congrés
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      Este artículo presenta una extensión de nuestro método CQC destinada a comprobar la contención de dos consultas en el contexto de una BD relacional que puede contener valores nulos en los atributos de sus tuplas. Teniendo ...

    • Logic foundations of the OCL modelling language 

      Franconi, Enrico; Mosca, Alessandro; Oriol Hilari, Xavier; Rull, Guillem; Teniente López, Ernest (Springer, 2014)
      Comunicació de congrés
      Accés restringit per política de l'editorial
      In this paper we define the first-order fragment of the Object Constraint Language (OCL), the declarative language for describing rules that apply to conceptual schemas in the Unified Modelling Language (UML). This fragment ...

    • OCLFO: first-order expressive OCL constraints for efficient integrity checking 

      Franconi, Enrico; Mosca, Alessandro; Oriol Hilari, Xavier; Rull, Guillem; Teniente López, Ernest (2019-08)
      Article
      Accés obert
      OCL is the standard language for defining constraints in UML class diagrams. Unfortunately, as we show in this paper, full OCL is so expressive that it is not possible to check general OCL constraints efficiently. In ...

    • Ontology-based mappings 

      Mecca, Giansalvatore; Rull, Guillem; Santoro, Donatello; Teniente López, Ernest (Elsevier, 2015-07-01)
      Article
      Accés obert
      Data translation consists of the task of moving data from a source database to a target database. This task is usually performed by developing mappings, i.e. executable transformations from the source to the target schema. ...

    • The EPNet Project. Production and distribution of food during the Roman Empire: Economics and Political Dynamics 

      Remesal, José; Díaz-Guilera, Albert; Rondelli, Bernardo; Rubio, Xavier; Aguilera, Antonio; Martín-Arroyo, Daniel; Mosca, Alessandro; Rull, Guillem (Sapienza Università Editrice, 2014)
      Text en actes de congrés
      Accés obert
      The EPNet project aims to examine the framework of the Roman economic organisation and its networks by analysing epigraphical data from amphorae. This aim is to be realised through complex network analysis, model building ...

    • TINTIN : comprobación incremental de aserciones SQL 

      Oriol Hilari, Xavier; Teniente López, Ernest; Rull, Guillem (2016)
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      Ninguno de los SGBD más populares del momento implementa aserciones SQL, obligando así a implementar manualmente su comprobación. Por ello, presentamos TINTIN: una aplicación que genera automáticamente el código SQL para ...

    • TINTIN: a Tool for INcremental INTegrity checking of Assertions in SQL Server 

      Oriol Hilari, Xavier; Teniente López, Ernest; Rull, Guillem (2016)
      Comunicació de congrés
      Accés obert
      We present TINTIN, a tool to perform efficient integrity checking of SQL assertions in SQL Server. TINTIN rewrites each assertion into a set of standard SQL queries that, given a set of insertions and deletions of tuples, ...

    • Validation of mappings between schemas 

      Rull, Guillem; Farré Tost, Carles; Teniente López, Ernest; Urpí Tubella, Antoni (2007-06)
      Report de recerca
      Accés obert
      Mappings between schemas are key elements in several contexts such as data exchange, data integration, peer data management systems, etc. In all these contexts, the process of designing a mapping requires the participation ...