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A Comprehensive Analysis of Materialized Views in a Data Warehouse Environment

Garima Thakur, Anjana Gosain
2011 International Journal of Advanced Computer Science and Applications  
In fact, data preserved in a warehouse along with these materialized views must also be updated and maintained so that they can deal with the changes in data sources as well as the requirements stated  ...  Data in a warehouse can be perceived as a collection of materialized views that are generated as per the user requirements specified in the queries being generated against the information contained in  ...  The tasks involved in evolution of materialized views in a data warehouse can be categorized as follows: A.  ... 
doi:10.14569/ijacsa.2011.020513 fatcat:cp4pawfcfbaipdnu2btd22v6si

Towards quality-oriented data warehouse usage and evolution

Panos Vassiliadis, Mokrane Bouzeghoub, Christoph Quix
2000 Information Systems  
This problem is typically illustrated by the physical design of the data warehouse where the problem is to find a set of materialized views that optimize the response time of user requests and the global  ...  Furthermore, we prove how the quality management of the data warehouse can guide the process of data warehouse evolution, by tracking the interrelationships between the components of the data warehouse  ...  One can think of the quality factors as materialized views over the metadata and data of the warehouse; thus the evolution of the data warehouse can be seen as a view maintenance problem on the aggregated  ... 
doi:10.1016/s0306-4379(00)00011-9 fatcat:nrqvanen7fe7larrnhv3zz6mxe

Towards Quality-Oriented Data Warehouse Usage and Evolution [chapter]

Panos Vassiliadis, Mokrane Bouzeghoub, Christoph Quix
1999 Lecture Notes in Computer Science  
This problem is typically illustrated by the physical design of the data warehouse where the problem is to find a set of materialized views that optimize the response time of user requests and the global  ...  Furthermore, we prove how the quality management of the data warehouse can guide the process of data warehouse evolution, by tracking the interrelationships between the components of the data warehouse  ...  One can think of the quality factors as materialized views over the metadata and data of the warehouse; thus the evolution of the data warehouse can be seen as a view maintenance problem on the aggregated  ... 
doi:10.1007/3-540-48738-7_13 fatcat:w4jrnx7lobadnocsjsbqoez63a

Detecting Redundancy in Data Warehouse Evolution [chapter]

Dimitri Theodoratos
1999 Lecture Notes in Computer Science  
The evolution of a DW can result in a redundant set of materialized views.  ...  A Data Warehouse DW can be abstractly seen as a set of materialized views de ned over a set of remote data sources. A DW i s intended to satisfy a set of queries.  ...  This procedure is used for designing a method that detects redundant views in a given materialized view selection.  ... 
doi:10.1007/3-540-47866-3_23 fatcat:mrf65evq2rgm3igptkd4zoq3nm

Design and management of data warehouses report on the DMDW'99 workshop

Stella Gatziu, Manfred Jeusfeld, Martin Staudt, Yannis Vassiliou
1999 SIGMOD record  
Materialized views inside the data warehouse can potentially be reused during query evaluation.  ...  The warehouse cache can contain precomputed data either already specified at design time (as materialized views) or based on the actual data warehouse usage.  ... 
doi:10.1145/344816.344825 fatcat:k7qsj5w3o5dejpk4hufm75wpua

Data warehouse process management

Panos Vassiliadis, Christoph Quix, Yannis Vassiliou, Matthias Jarke
2001 Information Systems  
Finally, we exploit our framework to revert the widespread belief that data warehouses can be treated as collections of materialized views.  ...  the design, administration and especially evolution of a data warehouse.  ...  Why data warehouses are not (just) collections of materialized views Many database researchers have considered data warehouses to be collections of materialized views, organized in strata where the views  ... 
doi:10.1016/s0306-4379(01)00018-7 fatcat:on7huo45nbgynnily5mpknzzpq

Data Warehousing and Knowledge Discovery: A Chronological View of Research Challenges [chapter]

Tho Manh Nguyen, A Min Tjoa, Juan Trujillo
2005 Lecture Notes in Computer Science  
In the early 2000 the research community gradually solve the most basic issues in data warehouse design, materialized view maintenance and selection, OLAP query design and evolution.  ...  It is even imaginable that in the medium-term future the separation of OLAP-data warehouses (with its semantic redundant storage requirement) from its OLTP-database-sources could be bridge by innovative  ... 
doi:10.1007/11546849_52 fatcat:sdcervokrzasvanqlcnbp4jsp4

A data warehouse to support web site automation

Marcos Aurélio Domingues, Carlos Soares, Alípio Mário Jorge, Solange Oliveira Rezende
2014 Journal of the Brazilian Computer Society  
Result: The case studies showed that our data warehouse is appropriate for web site automation in different contexts.  ...  Conclusion: In all cases, the use of the data warehouse was quite simple and with a good response time, mainly because of the simplicity of its structure.  ...  From the point of view of the owner (the entity that materially supports the site), the need for such a constant labor-intensive effort implies very high financial and personnel costs.  ... 
doi:10.1186/1678-4804-20-11 fatcat:mlw6wdpe3fejdnfeglgl7iz764

Enterprise modeling and Data Warehousing in Telecom Italia

Diego Calvanese, Luigi Dragone, Daniele Nardi, Riccardo Rosati, Stefano M. Trisolini
2006 Information Systems  
on the information stored in the Warehouse.  ...  We present a methodology for Data Warehouse design and its application within the TELECOM ITALIA information system.  ...  we want to materialize in the table of the Data Warehouse, and thus of the mediator for loading such a materialized view.  ... 
doi:10.1016/j.is.2004.07.002 fatcat:qsdcmq6lczht3oghesuuwphbne

Quantifying the Connectivity of a Semantic Warehouse and Understanding its Evolution over Time

Michalis Mountantonakis, Nikos Minadakis, Yannis Marketakis, Pavlos Fafalios, Yannis Tzitzikas
2016 International Journal on Semantic Web and Information Systems (IJSWIS)  
In addition, we show how the metrics can be used for monitoring a semantic warehouse after each reconstruction reducing thereby the cost of quality checking, as well as for understanding its evolution  ...  We demonstrate the behavior of these metrics in the context of a real and operational semantic warehouse, as well as on synthetically produced warehouses.  ...  Furthermore, the proposed metrics can even detect redundant sources and sources containing data which are not connected with data found in the other sources.  ... 
doi:10.4018/ijswis.2016070102 fatcat:ks2hdn2wmze6vpvr6lrie5dkzy

Policy-Regulated Management of ETL Evolution [chapter]

George Papastefanatos, Panos Vassiliadis, Alkis Simitsis, Yannis Vassiliou
2009 Lecture Notes in Computer Science  
In this paper, we discuss the problem of performing impact prediction for changes that occur in the schema/structure of the data warehouse sources.  ...  We abstract Extract-Transform-Load (ETL) activities as queries and sequences of views.  ...  Finally, the results are stored in the data warehouse (DW) either in fact or dimension tables and materialized views.  ... 
doi:10.1007/978-3-642-03098-7_6 fatcat:3lp6bymxczaeplhmiqplpnbs4u

Handling Evolution in Big Data Architectures

Darja Solodovnikova, Laila Niedrite
2020 Baltic Journal of Modern Computing  
However, innovative methods must be developed also to support evolution in Big Data systems.  ...  The problem of adapting data warehouse data and schemata to changes in user requirements and data sources has been studied by many researchers worldwide.  ...  These data are then used in the next analysis step and also deleted from the speed layer to avoid data redundancy.  ... 
doi:10.22364/bjmc.2020.8.1.02 fatcat:ghvrfrud7rcblj7a3ww3pzn2dm

Architecture and quality in data warehouses: An extended repository approach

Matthias Jarke, Manfred A. Jeusfeld, Christoph Quix, Panos Vassiliadis
1999 Information Systems  
Architecture and quality in data warehouses -An extended repository approach Jarke, M.; Jeusfeld, M.A.; Quix, C.; Vassiliadis, P.  ...  The resulting standardized and integrated data are stored as materialized views in the data warehouse.  ...  Physically, a data warehouse system consists of databases (source databases, materialized views in the data warehouse), data transport agents that ship data from one database to another, and a repository  ... 
doi:10.1016/s0306-4379(99)00017-4 fatcat:sphbss3ikjdhflleh7vzvdusgi

Handling multiple points of view in a multimedia data warehouse

Anne-Muriel Arigon, Anne Tchounikine, Maryvonne Miquel
2006 ACM Transactions on Multimedia Computing, Communications, and Applications (TOMCCAP)  
Data warehouses are dedicated to collecting heterogeneous and distributed data in order to perform decision analysis.  ...  With this approach, the user is able to obtain and choose multiple points of view on the data he analyses.  ...  Views or parts of views thus do not represent useful data for the user. In this case, these views should not be materialized so as to allow materialization of more useful views.  ... 
doi:10.1145/1152149.1152152 fatcat:coddhin34rhc3l6q3kuuo4w6yq

Benchmarking ETL Workflows [chapter]

Alkis Simitsis, Panos Vassiliadis, Umeshwar Dayal, Anastasios Karagiannis, Vasiliki Tziovara
2009 Lecture Notes in Computer Science  
Extraction-Transform-Load (ETL) processes comprise complex data workflows, which are responsible for the maintenance of a Data Warehouse.  ...  In this paper, we identify common characteristics of ETL workflows in an effort of proposing a unified evaluation method for ETL.  ...  The contents of the delta file are appended in the warehouse relation DW.PS.At the same time, the materialized view View04 is refreshed too.  ... 
doi:10.1007/978-3-642-10424-4_15 fatcat:mzyiwt6iwbgghkpsbgxhp7yo2y
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