What is the difference between view and materialised view?
Answers were Sorted based on User's Feedback
Answer / deepika
a view is like window through which we can acess the data.
it doesnot store the data,where as materialized view can
contain data also.this can be used for pre computed complex
calulations.
materialized views are called snapshots before oracle 9i
Is This Answer Correct ? | 8 Yes | 0 No |
Answer / anurag arun edlabadkar
Difference Between Inline View & Materialized View?
You can use Materialized views to pre-aggregate the data
and improve the query performance. When you create a
materialized view, Oracle created a physical table to hold
data that would usually be read via a view. When you create
a materialized view, you specify the view's base query as
well as a schedule for the refreshes of its data. You can
then index the materialized view to enhance the performance
of queries against it. As a result, you can provide data to
your user in the format they need, indexed appropriately.
A View is a database object that is a logical
Representation of of a table. It is derived from a table
but has no storage of its own and often may be used in the
same manner as a table.
Is This Answer Correct ? | 5 Yes | 0 No |
Answer / msb.dwh
a view is virtual or logical table it doesnot contain any
data but,m.view haveing data it also act like table m.view
mainly used for replication,computation,mentanience and
distrubuting the data these are equl to table or partation
table wich work like indexs
Is This Answer Correct ? | 4 Yes | 0 No |
Answer / sarvesh
VIEW IS THE VIRTTUAL TABLE,AND WE CANOT REFRESH THE
DATA ,BUT IN MATERIALISED VIEW WE CAN REFRESH THE DATA
FREQUNENTLY,AND BY USING M.VIEW THE PERFORMANCE WILL BE
INCREASED.
Is This Answer Correct ? | 4 Yes | 2 No |
Answer / 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.
Is This Answer Correct ? | 2 Yes | 0 No |
Answer / yaseen
Rowid of view and table is same
Rowid of M.view and table is different
Is This Answer Correct ? | 0 Yes | 0 No |
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