Materialized view: A scenario where we need to fetch data from a remote end (database) , we can go for creation of a materialized view on remote database.
For example, an inventory system maintains ESN (Equipment serial no) status as active, disconnected or churned in a database.
Now finance dept wants the latest updates or changes made with the status of ESN and created a materialized view on remote database.
A simple view does not hold memory space. Whereas materialized view holds memory space for whole data taken from other remote database.
Materialized view is of two types: fast refresh and complete refresh.
In case of fast refresh, data which are part of DML operation are taken into consideration for updating.
Whereas in case of complete refresh, whole data get update.
The materialized view created on a database, with fast refresh, where DML operations are very much frequent, raises the CPU utilization.