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Alex
If you do not specify the UNDO TABLESPACE when creating the database then AUTOEXTEND is set to ON. I was able to alter that to OFF.
The point of the UNDO is that it is automatically managed by Oracle. If you can't cope with that, or you decide that doesn't work well for you, then you can revert to the old manual ROLLBACK segments. I think that few sites had their rollback segments properly configured, and Oracle has been criticized for requiring a lot of expert attention compared to other databases. This is Oracle's attempt to reduce the TCO (Total Cost of Ownership).
Dennis Williams
DBA, 40%OCP, 100% DBA
Lifetouch, Inc.
dwilliams_at_lifetouch.com
-----Original Message-----
Sent: Sunday, March 16, 2003 10:59 PM
To: Multiple recipients of list ORACLE-L
How about UNDO tablespace in 9.2?
It gets created with "autoallocate", and there is no way to change it or
specify any parameters for undo segments.
Each segment extended as needed, and when shrinked deallocated some extents
not necessary the last, than allocate new extent.
Alex.
You do get odd results. The last time I tested on a clean tablespace, an initial of 65MB gave me a consistent result which I recall as:
Extent 0 at 8MB Extents 1 - 56 at 1MB each Extent 57 at 8MB
case
when initial_extent < 1m then case when extents < 16 then next = 64k, when extents < 80 then next = 1m, when extents < 200 then next = 8m, else next = 64m when initial_extent >= 1m then case when extents < 64 then next = 1m, when extents < 184 then next = 8m, else next = 64m )
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--
Author: Alex Feinstein
INET: alexf1_at_san.rr.com
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Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services ---------------------------------------------------------------------To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). Received on Mon Mar 17 2003 - 08:28:40 CST