Answer Posted / rameshbabu.katikireddy
In literature on data warehousing are created in Oracle using a schema object called a materialized view. Materialized views can be used to perform a number of roles, such as improving query performance or providing replicated data, as described below.
In data warehouses, materialized views can be used to recompute and store aggregated data such as sum of sales. Materialized views in these environments are typically referred to as summaries since they store summarized data. They can also be used to recompute joins with or without aggregations. So a materialized view is used to eliminate overhead associated with expensive joins or aggregations for a large or important class of queries.
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Rameshbabu.katikireddy
Time:jan.11.2012,6:20pm
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