Question about undo


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?

.

Relevant Pages

  • Re: UNDOTBS
    ... that for the UNDO tablespace AUTOEXTEND is OFF. ... Otherwise Oracle allocates new extents beforetrying to overwrite obsolete segments. ... We have a large update script which filled up about 80% of a 20G ...
    (comp.databases.oracle.server)
  • Re: undo retention
    ... Yes, but it is only keeping change vectors, so ... Oracle needs to be able to reconstruct any blocks it accesses as they ... transaction needs to be able to see what the db looked like at the ... data values changed by the update are recorded in the database undo ...
    (comp.databases.oracle.misc)
  • Re: Question about undo
    ... We just migrated to Oracle 10g, ... The documentation states that the UNDO table space keeps the ... Does this mean that the rollback segments are no longer used and can ...
    (comp.databases.oracle.server)
  • Re: undo tablespace keeps growing, why cant I reclaim space?
    ... I'm looking for an explanation for the excessive use of undo space. ... undo segments were designed to work like temporary segments. ... This is to be expected as Oracle and several ... > transaction is 40G. ...
    (comp.databases.oracle.server)
  • Re: UNDO: 10g-style behaviour in 9.2.0.8?
    ... available space in the UNDO tablespace is restricted (autoextend off), ... SQLTools++ for Oracle: ... For an AUTOEXTEND undo tablespace, the database tunes the undo retention ...
    (comp.databases.oracle.server)