Hi,
Materialized views are schema objects that can be used to summarize, compute, replicate, and distribute data. They are suitable in various computing environments such as data warehousing, decision support, and distributed or mobile computing:
In distributed environments, materialized views are used to replicate data at distributed sites and synchronize updates done at several sites with conflict resolution methods. The materialized views as replicas provide local access to data that otherwise has to be accessed from remote sites.
Materialized views are similar to indexes in several ways:
They consume storage space.
They must be refreshed when the data in their master tables changes.
They improve the performance of SQL execution when they are used for query rewrites.
Their existence is transparent to SQL applications and users.
Unlike indexes, materialized views can be accessed directly using a SELECT statement. Depending on the types of refresh that are required, they can also be accessed directly in an INSERT, UPDATE, or DELETE statement.
A materialized view can be partitioned. You can define a materialized view on a partitioned table and one or more indexes on the materialized view
A materialized view contains a complete or partial copy of a target master from a single point in time. The target master can be either a master table at a master site or a master materialized view at a materialized view site. A master materialized view is a materialized view that functions as a master for another materialized view. A multitier materialized view is one that is based on another materialized view, instead of on a master table.
It requires lot of experience thats it.
Regards
vinod
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