Re: Question about undo

artmerar@xxxxxxxxx wrote:
Hi,

We just migrated to Oracle 10g, from 8i. We had one question about
UNDO. The documentation states that the UNDO table space keeps the
'undo' information for whatever time you specify and then writes it to
disk.

Does this mean that the rollback segments are no longer used and can
be removed/deleted from the system/init.ora?

Basically, yes. As I understand it, one merely specifies an undo tablespace of sufficient size and lets oracle get on with it. Parameters are UNDO_MANAGEMENT=AUTO and UNDO_TABLESPACE. Forget rollback segments.

It's useful to look up UNDO_RETENTION too.

And btw, these days it's probably a good idea to use an spfile rather than an init.ora.

Palooka
.

Relevant Pages

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