(PDF) Materialización de Vistas Multi-Origen: Vistas Multinivel

A data warehouse is a large data repository for the purpose of analysis and decision making in organizations. To improve the query performance and to get fast access to the data, data is stored as materialized views (MV) in the data warehouse. When data at source gets updated, the materialized views also need to be updated. In this paper, we focus on the problem of maintenance of these materialized views and address the issue of finding such auxiliary views (AV) that together with the materialized views make the data self-maintainable and take minimal space. We propose an algorithm that uses key and referential constraints which reduces the total number of tuples in auxiliary views and uses idea of information sharing between these auxiliary views to further reduce number of auxiliary views. https://sites.google.com/site/ijcsis/

Quick response time and accuracy are important factors in the success of any database. In large databases particularly in distributed database, query response time plays an important role as timely access to information and it is the basic requirement of successful business application. A data warehouse uses multiple materialized views to efficiently process a given set of queries. The materialization of all views is not possible because of the space constraint and maintenance cost constraint. Materialized views selection is one of the crucial decisions in designing a data warehouse for optimal efficiency. Selecting a suitable set of views that minimizes the total cost associated with the materialized views is the key component in data warehousing. Materialized views are found useful for fast query processing. This paper gives the results of proposed tree based materialized view selection algorithm for query processing. In distributed environment where database is distributed the no...

A Data Warehouse is a computer system designed for archiving and analyzing an organization's historical data, such as sales, customers, products, salaries, or other information from day-today operations OLTP. Normally, an organization summarizes and copies information from its operational systems to the data warehouse on a regular schedule, such as daily, weekly, monthly, quarterly or annually; after that, management can perform complex queries and analysis OLAP on the information without slowing down the operational systems. Materialized views can be one best option in this regard and can be used in a number of ways. It can be used in distributed databases for replication and can also be used for efficient provision of data to a query through query rewriting. The process of data provision to queries can further be expedited if dependent child views are created on an already existing materialized view. Furthermore, these child-views are automatically created upon the creation of the base materialized view with some restrictions. This results in less-user dependent activity of creation of materialized views based on some parameters. These parameters are the number of child-materialized views and the type of the data a view contain. In this paper, a balanced approach is suggested to create sub-materialized views to answer user queries without consulting the fact table or parent materialized view that results in avoidance of resource intensive calculations and joining of multiple tables.

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Materialización de Vistas Multi-Origen: Vistas Multinivel

Materialización de Vistas Multi-Origen: Vistas Multinivel

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