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MR-Radix: a multi-relational data mining algorithm

Valêncio, Carlos ; Oyama, Fernando ; Scarpelini Neto, Paulo ; Colombini, Angelo ; Cansian, Adriano ; Souza, Rogéria de; Corrêa, Pedro Luiz Pizzigatti
Fonte: Biblioteca Digital da Produção Intelectual da USP Publicador: Biblioteca Digital da Produção Intelectual da USP
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
56.68%
Abstract Background Once multi-relational approach has emerged as an alternative for analyzing structured data such as relational databases, since they allow applying data mining in multiple tables directly, thus avoiding expensive joining operations and semantic losses, this work proposes an algorithm with multi-relational approach. Methods Aiming to compare traditional approach performance and multi-relational for mining association rules, this paper discusses an empirical study between PatriciaMine - an traditional algorithm - and its corresponding multi-relational proposed, MR-Radix. Results This work showed advantages of the multi-relational approach in performance over several tables, which avoids the high cost for joining operations from multiple tables and semantic losses. The performance provided by the algorithm MR-Radix shows faster than PatriciaMine, despite handling complex multi-relational patterns. The utilized memory indicates a more conservative growth curve for MR-Radix than PatriciaMine...

Proposta de um Framework de persistência de objetos em bases de dados objeto-relacional.; Propose of a objec t persistence Framework in object-relational databases.

Rombaldo Junior, Carlos Alberto
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 09/03/2012 PT
Relevância na Pesquisa
66.71%
Este trabalho apresenta o desenvolvimento de um Framework de persistência que utiliza banco de dados objeto-relacional como mecanismo de persistência. Tendo por objetivo usar os conceitos de orientação a objetos descritos na norma SQL:2008, conceitos como: objeto (atributos e métodos), herança, agregação, composição, referências (REF) e estruturas multivaloradas (arrays e multiset). Para tanto se desenvolveu e formalizou (XSD) um arquivo XML que representa um esquema de objetos através da norma SQL:2008. Da mesma forma definiu-se um conjunto de anotações Java, com o intuito de facilitar a utilização e configuração do Framework, o qual é chamado de O-ODBM (Object Object-Relational Database Management).; Persistent Frameworks have been used to aid developers, managing all access to DBMS. This kind of tool maps objects from OO applications to relational databases. Besides, allow developers to persist objects without solid knowledge about DBMSs and specific languages, making better the developers productivity, mainly when different DBMS is used. On the other hands, since 1999 the SQL specification has introduced new features to manipulate objects in relational databases which since then has been called Object-Relational Database (ORDB). At present...

Análise visual de dados relacionais: uma abordagem interativa suportada por teoria dos grafos; Visual analysis of relational databases: an interactive approach supported by graph theory

Lima, Daniel Mário de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 18/12/2013 PT
Relevância na Pesquisa
66.6%
Bancos de dados relacionais são fontes de dados rigidamente estruturadas, caracterizadas por relacionamentos complexos entre um conjunto de relações (tabelas). Entender tais relacionamentos é um desafio, porque os usuários precisam considerar múltiplas relações, entender restrições de integridade, interpretar vários atributos, e construir consultas SQL para cada tentativa de exploração. Neste cenário, introduz-se uma metodologia em duas etapas; primeiro utiliza-se um grafo organizado como uma estrutura hierárquica para modelar os relacionamentos do banco de dados, e então, propõe-se uma nova técnica de visualização para exploração relacional. Os resultados demonstram que a proposta torna a exploração de bases de dados significativamente simplificada, pois o usuário pode navegar visualmente pelos dados com pouco ou nenhum conhecimento sobre a estrutura subjacente. Além disso, a navegação visual de dados remove a necessidade de consultas SQL, e de toda complexidade que elas requerem. Acredita-se que esta abordagem possa trazer um paradigma inovador no que tange à compreensão de dados relacionais; Relational databases are rigid-structured data sources characterized by complex relationships among a set of relations (tables). Making sense of such relationships is a challenging problem because users must consider multiple relations...

From XML to relational view updates: applying old solutions to solve a new problem; De atualizações sobre visões XML para atualizações sobre visões relacionais: aplicando soluções antigas a um novo problema

Braganholo, Vanessa de Paula
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Tese de Doutorado Formato: application/pdf
ENG
Relevância na Pesquisa
56.77%
XML has become an important medium for data exchange, and is frequently used as an interface to - i.e. a view of - a relational database. Although lots of work have been done on querying relational databases through XML views, the problem of updating relational databases through XML views has not received much attention. In this work, we give the rst steps towards solving this problem. Using query trees to capture the notions of selection, projection, nesting, grouping, and heterogeneous sets found throughout most XML query languages, we show how XML views expressed using query trees can be mapped to a set of corresponding relational views. Thus, we transform the problem of updating relational databases through XML views into a classical problem of updating relational databases through relational views. We then show how updates on the XML view are mapped to updates on the corresponding relational views. Existing work on updating relational views can then be leveraged to determine whether or not the relational views are updatable with respect to the relational updates, and if so, to translate the updates to the underlying relational database. Since query trees are a formal characterization of view de nition queries, they are not well suited for end-users. We then investigate how a subset of XQuery can be used as a top level language...

Comparative study of algorithms for mining association rules: Traditional approach versus multi-relational approach

Valêncio, Carlos Roberto; Oyama, Fernando Takeshi; Neto, Paulo Scarpelini; De Souza, Rogéria Cristiane Gratão
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 275-280
ENG
Relevância na Pesquisa
56.71%
The multi-relational Data Mining approach has emerged as alternative to the analysis of structured data, such as relational databases. Unlike traditional algorithms, the multi-relational proposals allow mining directly multiple tables, avoiding the costly join operations. In this paper, is presented a comparative study involving the traditional Patricia Mine algorithm and its corresponding multi-relational proposed, MR-Radix in order to evaluate the performance of two approaches for mining association rules are used for relational databases. This study presents two original contributions: the proposition of an algorithm multi-relational MR-Radix, which is efficient for use in relational databases, both in terms of execution time and in relation to memory usage and the presentation of the empirical approach multirelational advantage in performance over several tables, which avoids the costly join operations from multiple tables. © 2011 IEEE.

MR-Radix: a multi-relational data mining algorithm

Valencio, Carlos R.; Oyama, Fernando T.; Scarpelini, Paulo; Colombini, Angelo C.; Souza, Rogeria C. G. de; Cansian, Adriano Mauro
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
56.68%
Background: Once multi-relational approach has emerged as an alternative for analyzing structured data such as relational databases, since they allow applying data mining in multiple tables directly, thus avoiding expensive joining operations and semantic losses, this work proposes an algorithm with multi-relational approach. Methods: Aiming to compare traditional approach performance and multi-relational for mining association rules, this paper discusses an empirical study between PatriciaMine - an traditional algorithm - and its corresponding multi-relational proposed, MR-Radix. Results: This work showed advantages of the multi-relational approach in performance over several tables, which avoids the high cost for joining operations from multiple tables and semantic losses. The performance provided by the algorithm MR-Radix shows faster than PatriciaMine, despite handling complex multi-relational patterns. The utilized memory indicates a more conservative growth curve for MR-Radix than PatriciaMine, which shows the increase in demand of frequent items in MR-Radix does not result in a significant growth of utilized memory like in PatriciaMine. Conclusion: The comparative study between PatriciaMine and MR-Radix confirmed efficacy of the multi-relational approach in data mining process both in terms of execution time and in relation to memory usage. Besides that...

Relational databases digital preservation

Freitas, Ricardo André Pereira; Ramalho, José Carlos
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em //2009 ENG
Relevância na Pesquisa
66.66%
Digital preservation is emerging as an area of work and research that tries to provide answers that will ensure a continued and long-term access to information stored digitally. IT Platforms are constantly changing and evolving and nothing can guarantee the continuity of access to digital artifacts in their absence. This paper focuses on a speci c family of digital objects: Relational Databases; they are the most frequent type of databases used by organizations worldwide. A neutral format that is hardware and software independent is the key to achieve a standard format to use in digital preservation of relational databases. XML for its neutrality was chosen for this representation of the database. The presented solution o ers a possibility to achieve relational databases preservation. The prototype follows the "Reference Model for an Open Archival Information System" (OAIS).

Significant properties in the preservation of relational databases

Freitas, Ricardo André Pereira; Ramalho, José Carlos
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em /09/2010 ENG
Relevância na Pesquisa
66.6%
Relational Databases are the most frequent type of databases used by organizations worldwide and are the base of several information systems. As in all digital objects, and concerning the digital preservation of them, the signi cant properties (signi cant characteristics) must be de ned so that adopted strategies are appropriate. In previous work a neutral format (hardware and software independent) | DBML | was adopted to achieve a standard format used in the digital preservation of the relational databases data and structure. In this paper we walk further in the de nition of the signi cant properties by considering the database semantics as an important characteristic that should be also preserved. For the representation of this higher level of abstraction we are going to use an ontology based approach. We will extract the entityrelationship model from the DBML representation and we will represent it as an ontology.

Preservation of relational databases : significant properties in the preservation of relational databases

Freitas, Ricardo André Pereira; Ramalho, José Carlos
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Artigo de Revista Científica
Publicado em 13/07/2011 ENG
Relevância na Pesquisa
66.66%
Relational Databases are the most frequent type of databases used by organizations worldwide and are the base of several information systems. As in all digital objects, and concerning the digital preservation of them, the significant properties (significant characteristics) must be defined so that adopted strategies can be evaluated. First, a neutral format (hardware and software independent) – DBML – was adopted to persue the goal of dematerialization and to achieve a standard format in the digital preservation of the relational databases data and structure. Currently, in this project, we walk further in the definition of the significant properties by considering the database semantics as an important characteristic that should also be preserved. For the representation of this higher level of abstraction we are going to use an ontology based approach. We extract the entity-relationship model from the database in order to represent it as an ontology.

Significant properties in the preservation of relational databases

Freitas, Ricardo André Pereira; Ramalho, José Carlos
Fonte: IEEE-TCDL Publicador: IEEE-TCDL
Tipo: Artigo de Revista Científica
Publicado em /09/2011 ENG
Relevância na Pesquisa
66.6%
Relational Databases are the most frequent type of databases used by organizations worldwide and are the base of several information systems. As in all digital objects, and concerning the digital preservation of them, the significant properties (significant characteristics) must be defined so that adopted strategies are appropriate. In previous work a neutral format (hardware and software independent) — DBML — was adopted to achieve a standard format used in the digital preservation of the relational databases data and structure. Currently, in this PhD project we walk further in the definition of the significant properties by considering the database semantics as an important characteristic that should also be preserved. For the representation of this higher level of abstraction we are going to use an ontology based approach. We will extract the entity-relationship model from the DBML representation and we will represent it as an ontology.

New dimension in relational database preservation : raising the abstraction level

Freitas, Ricardo André Pereira; Ramalho, José Carlos
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Artigo de Revista Científica
Publicado em /11/2011 ENG
Relevância na Pesquisa
56.64%
The work addressed in this paper focuses on the preserva- tion of the conceptual model within a specific class of dig- ital objects: Relational Databases. Previously, a neutral format was adopted to pursue the goal of platform inde- pendence and to achieve a standard format in the digital preservation of relational databases, both data and struc- ture (logical model). Currently, in this project, we address the preservation of relational databases by focusing on the conceptual model of the database, considering the database semantics as an important preservation ”property”. For the representation of this higher layer of abstraction present in databases we use an ontology based approach. At this higher abstraction level exists inherent Knowledge associated to the database semantics that we tentatively represent using ”Web Ontology Language” (OWL). We developed a proto- type (supported by case study) and define a mapping algo- rithm for the conversion between the database and OWL. The ontology approach is adopted to formalize the knowl- edge associated to the conceptual model of the database and also a methodology to create an abstract representation of it.

Relational databases conceptual preservation

Freitas, Ricardo André Pereira; Ramalho, José Carlos
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em //2011 ENG
Relevância na Pesquisa
66.6%
Previously, a neutral format was adopted to pursue the goal of platform independence and to achieve a standard format in the digital preservation of relational databases, both data and structure (logical model). Currently, we intend to address the preservation of relational databases by focusing on the conceptual model of the database, considering the database semantics as an important preservation ”property”. For the representation of this higher level of abstraction present in databases we use an ontology based approach. At this higher abstraction level exists inherent Knowledge associated to the database semantics that we tentatively represent using ”Web Ontology Language” (OWL). We developed a prototype (supported by case study) and define a mapping algorithm for the conversion between the database and OWL.

Using ontologies to abstract relational databases conceptual model

Freitas, Ricardo André Pereira; Ramalho, José Carlos
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Artigo de Revista Científica
Publicado em 10/10/2011 ENG
Relevância na Pesquisa
66.66%
This paper addresses the problematic Digital Preservation and focuses on the conceptual model within a specific class of digital objects: Relational Databases. Previously, a neutral format was adopted to pursue the goal of platform independence and to achieve a standard format in the digital preservation of relational databases, both data and structure (logical model). Currently, in this project, we intend to address the preservation of relational databases by focusing on the conceptual model of the database, considering the database semantics as an impor- tant preservation ”property”. For the representation of this higher level of abstraction present in databases we use an ontology based approach. At this higher abstraction level exists inherent Knowledge associated to the database semantics that we tentatively represent using ”Web Ontol- ogy Language” (OWL). We developed a prototype (supported by case study) and define a mapping algorithm for the conversion between the database and OWL. The ontology approach is adopted to formalize the knowledge associated to the conceptual model of the database and also a methodology to create an abstract representation of it.

An Abstract Algebraic Theory of L-Fuzzy Relations for Relational Databases

Chowdhury, Abdul Wazed
Fonte: Brock University Publicador: Brock University
Tipo: Electronic Thesis or Dissertation
ENG
Relevância na Pesquisa
66.5%
Classical relational databases lack proper ways to manage certain real-world situations including imprecise or uncertain data. Fuzzy databases overcome this limitation by allowing each entry in the table to be a fuzzy set where each element of the corresponding domain is assigned a membership degree from the real interval [0…1]. But this fuzzy mechanism becomes inappropriate in modelling scenarios where data might be incomparable. Therefore, we become interested in further generalization of fuzzy database into L-fuzzy database. In such a database, the characteristic function for a fuzzy set maps to an arbitrary complete Brouwerian lattice L. From the query language perspectives, the language of fuzzy database, FSQL extends the regular Structured Query Language (SQL) by adding fuzzy specific constructions. In addition to that, L-fuzzy query language LFSQL introduces appropriate linguistic operations to define and manipulate inexact data in an L-fuzzy database. This research mainly focuses on defining the semantics of LFSQL. However, it requires an abstract algebraic theory which can be used to prove all the properties of, and operations on, L-fuzzy relations. In our study, we show that the theory of arrow categories forms a suitable framework for that. Therefore...

Um Framework para construção de aplicações OO sobre SGBD relacional; Object-oriented application design in a relational database

Molz, Kurt Werner
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
56.69%
O paradigma da orientação a objetos esta se tomando a abordagem preferida para construção de sistemas em ambiente de banco de dados. Por outro lado, a tecnologia relacional e amplamente adotada para gerenciar dados corporativos. Os bancos de dados relacionais tornaram-se o padrão no armazenamento de dados para aplicações de processamento de transações on-line (OLTP). Estas tendências estão motivando a necessidade de construção de aplicações orientadas a objetos que acessem banco de dados relacionais. 0 uso de conceitos orientado a objetos, como herança, permitem uma modelagem !Dais adequada e uma melhor implementação da aplicação baseada em sistema de banco de dados orientado a objetos. Entretanto, os resultados do projeto orientado a objetos, podem também ser aplicados em sistemas clássicos de banco de dados. 0 trabalho apresenta o uso de padrões de projeto na construção de una arquitetura de um framework que auxilie o mapeamento de uma aplicação 00 a um SGBD relacional. Esta arquitetura segue a abordagem de persistência de objetos baseada em gateways, que é uma camada de software inserida entre o sistema gerenciador de banco de dados e a aplicação orientada a objetos, cujo o objetivo é dar suporte a um modelo de programação de aplicações 00. A característica principal desta arquitetura é a separação clara das classes que tratam da base de dados em relação as classes que tratam do domínio do problema da aplicação. Esta divisão de responsabilidades permite a substituição das classes referentes a base de dados por outras...

Strong types for relational databases : functional pearl

Visser, J.; Silva, Alexandra M.
Fonte: ACM Press Publicador: ACM Press
Tipo: Conferência ou Objeto de Conferência
Publicado em //2006 ENG
Relevância na Pesquisa
66.6%
Haskell's type system with multi-parameter constructor classes and functional dependencies allows static (compile-time) computations to be expressed by logic programming on the level of types. This emergent capability has been exploited for instance to model arbitrary-length tuples (heterogeneous lists), extensible records, functions with variable length argument lists, and (homogenous) lists of statically fixed length (vectors).We explain how type-level programming can be exploited to define a strongly-typed model of relational databases and operations on them. In particular, we present a strongly typed embedding of a significant subset of SQL in Haskell. In this model, meta-data is represented by type-level entities that guard the semantic correctness of database operations at compile time.Apart from the standard relational database operations, such as selection and join, we model functional dependencies (among table attributes), normal forms, and operations for database transformation. We show how functional dependency information can be represented at the type level, and can be transported through operations. This means that type inference statically computes functional dependencies on the result from those on the arguments.Our model shows that Haskell can be used to design and prototype typed languages for designing...

An Approach for Normalizing Fuzzy Relational Databases Based on Join Dependency

S, Deepa
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/03/2014
Relevância na Pesquisa
56.71%
Fuzziness in databases is used to denote uncertain or incomplete data. Relational Databases stress on the nature of the data to be certain. This certainty based data is used as the basis of the normalization approach designed for traditional relational databases. But real world data may not always be certain, thereby making it necessary to design an approach for normalization that deals with fuzzy data. This paper focuses on the approach for designing the fifth normal form (5NF) based on join dependencies for fuzzy data. The basis of join dependency for fuzzy relational databases is derived from the basic relational database concepts. As join dependency implies an multivalued dependency by symmetry the proof of join dependency based normalization is stated from the perspective of multivalued dependency based normalization on fuzzy relational databases.; Comment: 3 pages

On Directly Mapping Relational Databases to RDF and OWL (Extended Version)

Sequeda, Juan F.; Arenas, Marcelo; Miranker, Daniel P.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
56.64%
Mapping relational databases to RDF is a fundamental problem for the development of the Semantic Web. We present a solution, inspired by draft methods defined by the W3C where relational databases are directly mapped to RDF and OWL. Given a relational database schema and its integrity constraints, this direct mapping produces an OWL ontology, which, provides the basis for generating RDF instances. The semantics of this mapping is defined using Datalog. Two fundamental properties are information preservation and query preservation. We prove that our mapping satisfies both conditions, even for relational databases that contain null values. We also consider two desirable properties: monotonicity and semantics preservation. We prove that our mapping is monotone and also prove that no monotone mapping, including ours, is semantic preserving. We realize that monotonicity is an obstacle for semantic preservation and thus present a non-monotone direct mapping that is semantics preserving.

Scalable Continual Top-k Keyword Search in Relational Databases

XU, Yanwei
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 23/08/2011
Relevância na Pesquisa
56.68%
Keyword search in relational databases has been widely studied in recent years because it does not require users neither to master a certain structured query language nor to know the complex underlying database schemas. Most of existing methods focus on answering snapshot keyword queries in static databases. In practice, however, databases are updated frequently, and users may have long-term interests on specific topics. To deal with such a situation, it is necessary to build effective and efficient facility in a database system to support continual keyword queries. In this paper, we propose an efficient method for answering continual top-$k$ keyword queries over relational databases. The proposed method is built on an existing scheme of keyword search on relational data streams, but incorporates the ranking mechanisms into the query processing methods and makes two improvements to support efficient top-$k$ keyword search in relational databases. Compared to the existing methods, our method is more efficient both in computing the top-$k$ results in a static database and in maintaining the top-$k$ results when the database continually being updated. Experimental results validate the effectiveness and efficiency of the proposed method.

Structural advances for pattern discovery in multi-relational databases

Kanodia, Juveria
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado Formato: 15299 bytes; 1045261 bytes; 148995 bytes; 1 bytes; 2061 bytes; 698 bytes; 5468 bytes; 49 bytes; 15299 bytes; 1045261 bytes; application/pdf; application/pdf; text/plain; text/plain; text/plain; application/octet-stream; application/octet-stream; applicati
EN_US
Relevância na Pesquisa
56.61%
With ever-growing storage needs and drift towards very large relational storage settings, multi-relational data mining has become a prominent and pertinent field for discovering unique and interesting relational patterns. As a consequence, a whole suite of multi-relational data mining techniques is being developed. These techniques may either be extensions to the already existing single-table mining techniques or may be developed from scratch. For the traditionalists, single-table mining algorithms can be used to work on multi-relational settings by making inelegant and time consuming joins of all target relations. However, complex relational patterns cannot be expressed in a single-table format and thus, cannot be discovered. This work presents a new multi-relational frequent pattern mining algorithm termed Multi-Relational Frequent Pattern Growth (MRFP Growth). MRFP Growth is capable of mining multiple relations, linked with referential integrity, for frequent patterns that satisfy a user specified support threshold. Empirical results on MRFP Growth performance and its comparison with the state-of-the-art multirelational data mining algorithms like WARMR and Decentralized Apriori are discussed at length. MRFP Growth scores over the latter two techniques in number of patterns generated and speed. The realm of multi-relational clustering is also explored in this thesis. A multi-Relational Item Clustering approach based on Hypergraphs (RICH) is proposed. Experimentally RICH combined with MRFP Growth proves to be a competitive approach for clustering multi-relational data. The performance and iii quality of clusters generated by RICH are compared with other clustering algorithms. Finally...