After Version Enabled (Workspace Manager) [message #432705] |
Wed, 25 November 2009 22:32 |
rakeshramm
Messages: 175 Registered: September 2006 Location: Oracle4u.com
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Senior Member |
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After I version enabled some my tables in database (Workspace Manager concept) . I feel there is some slowness in my application .Is there any option to increase performance after version enabled a table .
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Re: After Version Enabled (Workspace Manager) [message #432788 is a reply to message #432705] |
Thu, 26 November 2009 05:16 |
JRowbottom
Messages: 5933 Registered: June 2006 Location: Sunny North Yorkshire, ho...
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Senior Member |
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Quote:I feel there is some slowness in my application
If this is all you have to go on, then probably not.
Have you run any statspack/AWR reports to investigate the system performance?
Do you have any statspack/AWR reports prior to the Version to compare them with?
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Re: After Version Enabled (Workspace Manager) [message #432881 is a reply to message #432705] |
Fri, 27 November 2009 00:38 |
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Kevin Meade
Messages: 2103 Registered: December 1999 Location: Connecticut USA
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Senior Member |
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OWM (Oracle Workspace Manager) is expensive. It is a great concept, and Oracle does a good job of implementing the full workspace concept, but this requires a lot of logic in implementation. To see what I mean, have a look at their code.
OWM is Oracle's idea of HYPOTHETICAL VIEWS as written about by Stonebreaker and WoodFill et.al. some twenty years ago. Oracle does the magic they talked about by using VIEWS w/ INSTEAD-OF-TRIGGERS. Oracle creates views and triggers that are just like any other view/instead-of-trigger that you would create so you can look at the view text and triggers oracle creates on your behalf by examining DBA_VIEWS/DBA_TRIGGERS/DBA_SOURCE and you will see all the extra logic they added in order to implement a "WORKSPACE". You may wonder after looking at this stuff, how it goes as fast as it does.
It is all about what you want. Do you want Oracle's idea of workspaces? If so, how badly? Bad enough to pay the performance penalty? Bad enought to make your DBA's deal with the added administration when tables must be altered?
There is also a quirk (bug?) with instead-of-triggers when for some queries, oracle switches to a full table scan of the driving table in the query plan it creates. If you take the trigger away but issue the same query, the FTS goes away. I have asked oracle about it, but they are pulling the SHULTZ defense on me.
Good luck, Kevin
[Updated on: Fri, 27 November 2009 00:40] Report message to a moderator
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