Comparing Views, Tables, and Materialized Views
create or replace VIEW dept20_v as select * from emp where deptno = 20; create TABLE dept20_t as select * from emp where deptno = 20; create MATERIALIZED VIEW dept20_mv enable query rewrite as select * from emp where deptno = 20;
Materialized Views can store both its definition and the query results.
A materialized view has its own rows and stores redundant data.
Materialized views are "snapshots."
The Oracle optimizer may use the materialized views to rewrite query to make it faster.
When you create materialized views, you can specify whether you want to enable query rewrite.