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Home -> Community -> Mailing Lists -> Oracle-L -> RE: Table compression
Hi Leroy,
I use compression. Beware that adding a column requires uncompressing the table, adding the column, and re-compressing. Also, the percentage of compression you achieve can vary. If you do not use bulk insert, you will only receive nominal compression. If you do use bulk, you can get up to 40-50% compression. Even then it's not consistent, at least with the way I use it. .
I do not see my insert times increased with bulk loading and compressed tables as a target. Then again I am using pl/sql tables and insert into.. select from. The reponse time is reasonable and is still faster than non-direct.
I don't have any compressed indexes. I know it's possible, I just never implemented it.
HTH
Lisa Koivu
Oracle Database Monkey Mama
Orlando, FL, USA
-----Original Message-----
From: LeRoy Kemnitz [mailto:lkemnitz_at_uwsa.edu]
Sent: Friday, March 19, 2004 3:41 PM
To: Oracle List
Subject: Table compression
I am looking into doing some table compression on my warehouse database to free up some space on the os. I am running 9.2.0.4 on Unix 5.1. The
compression is about 2.5:1 on my tables. The documentation says the bulk insert time will be doubled but the single inserts, updates, and deletes are going to be a wash. Does anyone use compression? Are there
any problems you notice in the use of it? I have also read that the table will need to be re-compressed after the bulk inserts. Any alternative ideas about getting this done?
Thanks in advance,
LeRoy
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