What is the difference between view and materialised view?
Answer Posted / bhabna
1.Basically Materialize view is used as the local copy of a
remote table.So instead of using a remote table,we use M-
View to avoid the network trafic.
2. One of the most prominent feature of M-view is "ENABLE
QUERY REWRITE" clause.It is a query optimization
technique that transforms a user query written in terms of
tables and views, to execute faster by fetching data from
materialized views. It is completely transparent to the end
user, requiring no intervention or hints in the SQL
application because the Oracle9i server will automatically
rewrite any appropriate SQL application to use the
materialized views.
Where as view doesn't contain any such type of clause
3.View doesn't contains any data where as M-View does
4.View reflects the data whenever thae base table is
updated but M-view doesn't reflect that untill it is
refreshed.
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