What are the advantages of using materialized views in data warehouse than normal views?
I know some basic differences like below…
view is logical, will not occupy memory
materialized view is disc based, pre-computed aggregated data
I want to know why do we prefer mv against view, expecting some more differences from experts…
Thanks
Atik
Atik 
(BOB member since 2011-10-03)
Materialized views give you a speed advantage since the database does not have to execute the query each time it is called. The tradeoff is space and management of the MV. For example, overhead may become an issue it is set to update each time the base table(s) updates and you are running an OLTP data store. They can also serve as a cache (like HTTP caches) if you can allow clients to view stale data. This greatly reduces the amount of work your database needs to do.
BoB LoblaW 
(BOB member since 2007-10-23)
I asked related question a year ago.
Take a look at this: https://bobj-board.org/t/175037/5
Thanks,
Raghvendra
Raghvendra Deshpande (BOB member since 2008-05-26)