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Home -> Community -> Usenet -> c.d.o.misc -> Re: Never rebuild Indexes?
On Sun, 04 Feb 2007 20:12:05 +0000, Oradba Linux wrote:
> HansF wrote:
>>> Frank van Bortel wrote: >>>> Oradba Linux schreef: >>>>> We are running a 4 node RAC on RHEL 3.0. We have a table with 300mil >>>>> rows that has an pk index upto 12Gb and we rebuilt it it came down to >>>>> 6g. The data into this table was loaded with concurrent inserts from >>>>> different sessions. This table is on ASSM tablespace. Same thing with >>>>> many other indexes. >>>> Just wait a couple of weeks... >>>> >>> oh boy... You sound like a mystery novel. >>> >>> Do you feel it will bloat back up to 12G again. I am sure it will >>> increase but by how much is the question. I will not have any deletes to >>> this table. Many concurrent inserts from data loads.
Yes. As one of the reference books. I usually go to http://www.apress.com and look under the Oracle section for ISBNs for Tom's books. I personally prefer the discussions in his latest (Expert ... Architecture)
The point [I think] Frank is trying to make is: an index may have a natural size - for a specific %used/%free setting, blocksize and transaction pattern. Rebuilding may result in a significant savings in size, but if the settings/blocksize/transaction pattern are maintained, the index will eventually return to that natural size.
Better to understand what is driving that natural size than blindly rebuilding.
-- Hans Forbrich (mailto: Fuzzy.GreyBeard_at_gmail.com) *** Feel free to correct me when I'm wrong! *** Top posting [replies] guarantees I won't respond.Received on Sun Feb 04 2007 - 18:06:15 CST