Extending the Relational Algebra with the Mapper Operator
Autor(a) principal: | |
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Data de Publicação: | 2005 |
Outros Autores: | , , |
Tipo de documento: | Relatório |
Idioma: | por |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10451/14193 |
Resumo: | Application scenarios such as legacy data migration, Extract-Transform-Load (ETL) processes, and data cleaning require the transformation of input tuples into output tuples. Traditional approaches for implementing these data transformations enclose solutions as Persistent Stored Modules (PSM) executed by an RDBMS or transformation code using a commercial ETL tool. Neither of these is easily maintainable or optimizable. A third approach consists of combining SQL queries with external code, written in a programming language. However, this solution is not expressive enough to specify an important class of data transformations that produce several output tuples for a single input tuple. In this paper, we propose the data mapper operator as an extension to the relational algebra to address this class of data transformations. Furthermore, we supply a set of algebraic rewriting rules for optimizing expressions that combine standard relational operators with mappers. Finally, experimental results report the benefits brought by some of the proposed semantic optimizations |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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7160 |
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Extending the Relational Algebra with the Mapper OperatorApplication scenarios such as legacy data migration, Extract-Transform-Load (ETL) processes, and data cleaning require the transformation of input tuples into output tuples. Traditional approaches for implementing these data transformations enclose solutions as Persistent Stored Modules (PSM) executed by an RDBMS or transformation code using a commercial ETL tool. Neither of these is easily maintainable or optimizable. A third approach consists of combining SQL queries with external code, written in a programming language. However, this solution is not expressive enough to specify an important class of data transformations that produce several output tuples for a single input tuple. In this paper, we propose the data mapper operator as an extension to the relational algebra to address this class of data transformations. Furthermore, we supply a set of algebraic rewriting rules for optimizing expressions that combine standard relational operators with mappers. Finally, experimental results report the benefits brought by some of the proposed semantic optimizationsDepartment of Informatics, University of LisbonRepositório da Universidade de LisboaCarreira, Paulo J.F.Lopes, AntóniaGalhardas, HelenaPereira, João2009-02-10T13:11:39Z2005-012005-01-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/reportapplication/pdfhttp://hdl.handle.net/10451/14193porinfo:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-11-08T15:59:51Zoai:repositorio.ul.pt:10451/14193Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T21:36:01.631904Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Extending the Relational Algebra with the Mapper Operator |
title |
Extending the Relational Algebra with the Mapper Operator |
spellingShingle |
Extending the Relational Algebra with the Mapper Operator Carreira, Paulo J.F. |
title_short |
Extending the Relational Algebra with the Mapper Operator |
title_full |
Extending the Relational Algebra with the Mapper Operator |
title_fullStr |
Extending the Relational Algebra with the Mapper Operator |
title_full_unstemmed |
Extending the Relational Algebra with the Mapper Operator |
title_sort |
Extending the Relational Algebra with the Mapper Operator |
author |
Carreira, Paulo J.F. |
author_facet |
Carreira, Paulo J.F. Lopes, Antónia Galhardas, Helena Pereira, João |
author_role |
author |
author2 |
Lopes, Antónia Galhardas, Helena Pereira, João |
author2_role |
author author author |
dc.contributor.none.fl_str_mv |
Repositório da Universidade de Lisboa |
dc.contributor.author.fl_str_mv |
Carreira, Paulo J.F. Lopes, Antónia Galhardas, Helena Pereira, João |
description |
Application scenarios such as legacy data migration, Extract-Transform-Load (ETL) processes, and data cleaning require the transformation of input tuples into output tuples. Traditional approaches for implementing these data transformations enclose solutions as Persistent Stored Modules (PSM) executed by an RDBMS or transformation code using a commercial ETL tool. Neither of these is easily maintainable or optimizable. A third approach consists of combining SQL queries with external code, written in a programming language. However, this solution is not expressive enough to specify an important class of data transformations that produce several output tuples for a single input tuple. In this paper, we propose the data mapper operator as an extension to the relational algebra to address this class of data transformations. Furthermore, we supply a set of algebraic rewriting rules for optimizing expressions that combine standard relational operators with mappers. Finally, experimental results report the benefits brought by some of the proposed semantic optimizations |
publishDate |
2005 |
dc.date.none.fl_str_mv |
2005-01 2005-01-01T00:00:00Z 2009-02-10T13:11:39Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/report |
format |
report |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10451/14193 |
url |
http://hdl.handle.net/10451/14193 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Department of Informatics, University of Lisbon |
publisher.none.fl_str_mv |
Department of Informatics, University of Lisbon |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
instacron_str |
RCAAP |
institution |
RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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1799134258619482113 |