 |
|
Oracle UNDO tablespace with autoextend
Oracle Tips by Burleson Consulting |
Question:
What are the risks associated with using the
autoextend option on my UNDO tablespace?
Answer:
If you run out of UNDO you will get the message
"ORA-30036: unable to extend segment by 8192 in undo tablespace 'UNDOTBS'"
and the update will abort.
The size of your UNDO is governed by the total
space required to store the before images for your largest DML
transaction. The size of your UNDO is governed by the total
space required to store the before images for your largest DML
transaction.
Some DBA's use the "autoextend" option on their
UNDO tablespace, but you run the risk of running out of disk space
if you have a super-large update running, or a runaway update. Like
everything it Oracle, the choice us using autoextend for UNDO
depends on your system requirements. If your SLA requires you to
minimize aborts, it might be worth the risk of filling-up a disk.
 |
If you like Oracle tuning, you may enjoy my new book "Oracle
Tuning: The Definitive Reference", over 900 pages
of BC's favorite tuning tips & scripts.
You can buy it direct from the publisher for 30%-off and get
instant access to the code depot of Oracle tuning scripts. |
 |
|
Need an Oracle Health Check?
- Do you have
bad performance after an upgrade?
- Need to
certify that your database follows best practices?
BC Oracle performance gurus can quickly
certify every aspect of your
Oracle database and provide a complete verification that your database
is fully optimized. |
|
|
