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Performance Analysis of One-to-Many Data Transformations

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Detalhes bibliográficos
Resumo:Relational Database Systems often support activities like data warehousing, cleaning and integration. All these activities require performing some sort of data transformations. Since data often resides on relational databases, data transformations are often specified using SQL, which is based of relational algebra. However, many useful data transformations cannot be expressed as SQL queries due to limited expressive power of relational algebra. In particular, an important class of data transformations that produces several output tuples for a single input tuple cannot be expressed in that way. In this report, we analyze alternatives to process one-to-many data transformations using Relational Database Systems, and compare them in terms of expressiveness, optimizability and performance
Autores principais:Carreira, Paulo J.F.
Outros Autores:Galhardas, Helena; Pereira, João; Martins, Fernando; Silva, Mário J.
Assunto:Data Warehousing Data Cleaning Data Integration Query Optimization
Ano:2006
País:Portugal
Tipo de documento:relatório
Tipo de acesso:acesso aberto
Instituição associada:Universidade de Lisboa
Idioma:português
Origem:Repositório da Universidade de Lisboa
Descrição
Resumo:Relational Database Systems often support activities like data warehousing, cleaning and integration. All these activities require performing some sort of data transformations. Since data often resides on relational databases, data transformations are often specified using SQL, which is based of relational algebra. However, many useful data transformations cannot be expressed as SQL queries due to limited expressive power of relational algebra. In particular, an important class of data transformations that produces several output tuples for a single input tuple cannot be expressed in that way. In this report, we analyze alternatives to process one-to-many data transformations using Relational Database Systems, and compare them in terms of expressiveness, optimizability and performance