Impact on performance at the addition of materialized view logs at the tables?
I write a very complex query for a client of our database system transaction and this will require the creation of a materialized viewbecause, all attempts at development to make acceptable performance failed.I want to activate the fast refresh the MVIEW but I am confused about the consequences of the addition of the addition of materialized view logs to the base tables.
Some tables are large and involved in a large number of transactions and I wonder if the INSERT/update performance will be seriously affected by the presence of a newspaper mview.
Maybe it's a simple question, but I was unable to find an answer very clear in the literature.
Thanks for all the answers!
Chris Mills
Biotechnology data management consultant
There is an overload for the newspapers of the view materialized, a little less, but roughly on par with a trigger that writes to a table.
If it is an OLTP system where you do a lot of low-value transactions, the general expenses percentage is probably not particularly great, something in the range of 5-10% maybe (although, of course, by running tests in the development environment would be desirable). If there are loads in bulk, the impact of the percentage could be higher.
Justin
Tags: Database
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NaamaNaamas wrote:
No,
I already read this post!Then you read wrong:
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=====================================================
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======================================================
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======================================================
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======================================================
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Chanchal,
If you can read my original post carefully you may have noticed that all these restrictions will not apply in my case.
All,
In any case I found the solution to my problem.
There are a few additional restrictions for materialized views multilayer
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ROWID
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- Read-only materialized views
I've updated the underlying MV abc below and everything worked like a charm
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n.*, n.rowid noderowid, nt.rowid nodetyperowid
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and nt.nodetypeid in (1610000069,1610007267);
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