Indexes [message #50766] |
Fri, 05 April 2002 00:54 ![Go to next message Go to next message](/forum/theme/orafaq/images/down.png) |
nadella srikanth
Messages: 6 Registered: March 2002
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Junior Member |
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Hi,
We have a 50gb database an SAP. I would like to know for the CBO to work efficiently, should we regularly keep generating statistics or is it enough if we do it the first time?
Also do we have to drop indexes and rebuild them regularly so that they are upto date.
Thanks in Advance.
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Re: Indexes [message #50767 is a reply to message #50766] |
Fri, 05 April 2002 01:11 ![Go to previous message Go to previous message](/forum/theme/orafaq/images/up.png) ![Go to next message Go to next message](/forum/theme/orafaq/images/down.png) |
Shrikanth
Messages: 16 Registered: April 2002
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Junior Member |
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make sure your index segment and size is effectively
big enough to perform the index and sorting. YOu dont
have to built the index again . If your tables are
having performance problem check whether the traceing
is ON on the database level if it is ON just put it off
and try to analyze the table once.
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Re: Indexes [message #50774 is a reply to message #50766] |
Fri, 05 April 2002 04:35 ![Go to previous message Go to previous message](/forum/theme/orafaq/images/up.png) ![Go to next message Go to next message](/forum/theme/orafaq/images/down.png) |
Sanjay Bajracharya
Messages: 279 Registered: October 2001 Location: Florida
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Senior Member |
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We have a 40GB DW database. Analyzing is recommended whenever there is a major data load or the data changes drastically. To be on the safer side, I do the analyze every Saturday (cron) when the system is pretty much idle.
You do not need to drop/build the index regularly. If the performance is degrading, then it is recommended.
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Re: Indexes [message #50787 is a reply to message #50766] |
Sun, 07 April 2002 07:06 ![Go to previous message Go to previous message](/forum/theme/orafaq/images/up.png) |
Kishore
Messages: 45 Registered: September 2000
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Member |
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Yes, to make CBO perform well, you need to keep the statistics up to date. If lot of DML occurs then you need to rebuild indexes as frequently as possible. You can use 'online index rebuilds' if your system running on 8i and beyond. I hope this helps.
Thanks,
Kishore
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