What is the difference between view and materialised view?
Answers were Sorted based on User's Feedback
Answer / sindhu
View - store the SQL statement in the database and let you
use it as a table. Every time you access the view, the SQL
statement executes.
Materialized view - stores the results of the SQL in table
form in the database. SQL statement only executes once and
after that every time you run the query, the stored result
set is used. Pros include quick query results
Is This Answer Correct ? | 14 Yes | 0 No |
Answer / anju
materialized view can be used to precalculate the expensive
joins and aggregates prior to execution and the result is
stored in a table in database and can refer to it in
future. the adv of this is increse in performance.
view is nothing but an sql query stored. it will not store
data in tables
Is This Answer Correct ? | 5 Yes | 0 No |
Answer / atiric sofrware(raja)
Views contains query whenever execute views it has read from
base table
Where as Materialised views loading or replicated takes
place only once which gives you better query performance
Refresh materialised views
1.on commit
2. on demand
(Complete, never, fast, force)
Is This Answer Correct ? | 2 Yes | 0 No |
Answer / praveen kumar pendekanti
In view if we do any operation that may be changes in table
and viveversa.View dont have memery allocation.if we create
a view as 'v1' on emp table and then we delete the emp
table there by 'v1' name will be exist in view list, but
data will not be there, if we create the emp table once
again it will automatically link to that 'v1'view.
But in the case of M.views the changes that made in table
cannot be seen in M.view.M.views have separate memery
allocation if we delete the table the M.view will be there.
M.view is read only view,D.D.L oerations are not possible
on this M.view. M.view are used in dataware housing.
Is This Answer Correct ? | 1 Yes | 0 No |
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