A materialized view is a stored summary containing precomputed results (originating from an SQL select statement). Materialized views are schema objects that can be used to summarize, precomputed, replicate, and distribute data. E.g. to construct a data warehouse. A materialized view provides indirect access to table data by storing the results of a query in a separate schema object. Unlike an ordinary view, which does not take up any storage space or contain any data.

A materialized view can be stored in the same database as its base table(s) or in a different database. Materialized views stored in the same database as their base tables can improve query performance through query rewrites. Query rewrites are particularly useful in a data warehouse environment.