No. We cannot perform DML operations on Dual table. because we dont have the access permissions on that table.I say: But if we have access eg. sysdba we can
For security reasons we hide data from the database then we use Views.If there are more transactions on the base table then we use materialized views.
I say: a materialized view is a table withe the same structure like the under laying view access to it specially when the view has many joins becomes much faster. there is different methods to reupdate this materialized view. frequently with a special command or as soon the underlaying tables changes.
You can index this materialized view
New features of Oracle 9i are:
i)Merge statement ii) Flashback query iii) Function based indexes iv) Materialised View enhancement and......
