Using Materialized Views To Speed Up Data Warehousing
نویسندگان
چکیده
Running analytical queries directly against the huge raw data volume of a data warehouse results in unacceptable query performance. The solution to this problem is storing materialized views in the warehouse, which pre-aggregate the data and thus avoid raw data access and speed up queries. In this paper, at first the problems concerning the selection of the right pre-aggregations and their utilization are discussed. The main focus then is the maintenance of the pre-aggregates due to changes of the raw data. We emphasize the specific aspects of warehouse maintenance compared to common view maintenance and present a warehouse model optimized for speeding-up view maintenance.
منابع مشابه
Dynamic View Selection for OLAP
In a data warehousing environment, aggregate views are often materialized in order to speed up aggregate queries of online analytical processing (OLAP). Due to the increasing size of data warehouses, it is often infeasible to materialize all views. View selection, the task of selecting a subset of views to materialize based on updates and expectations of the query load, is an important and chal...
متن کاملWhat is the Data Warehousing Problem? (Are Materialized Views the Answer?)
A view is a derived relation defined in terms of base (stored) relations. A view can be materialized by storing the tuples of the view in the database. A materialized view provides fast access to data; the speed difference is critical in applications where the query rate is high and the views are complex or over data in remote databases, so that it is not feasible to recompute the view for ever...
متن کاملQOP: Proposed Framework for Materialized View Maintenance in Data Warehouse Evolution
A data warehouse is generally applied to discover and integrate data from independent data source. In data warehouse large numbers of materialized views are stored in order to provide fast access to the integrated data. Maintenance of materialized views is one of the critical tasks in warehousing environment. They must be up to date to ensure accurate results and also to speed up the query proc...
متن کاملMaking Aggregate Views Self-maintainable
Data in the warehouse can be seen as materialized views generated from the underlying multiple data sources. Materialized views are used to speed up query processing on large amounts of data. These views need to be maintained in response to updates in the source data. This is often done using incremental techniques that access data from underlying sources. In the data warehousing scenario, acce...
متن کاملReduction of Update Propagation Overhead for Data Warehousing Incorporating OODBs
Since the requirement of data warehouse is increasing, it is necessary to develop eflcient mechanisms for data warehouses incorporating various kinds of database systems. Essentially, materialized views are used for data warehouses and various methods for relational databases have been developed. In this paper, we will first discuss a method to realize materialized views for object-on’ented dat...
متن کامل