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Connor McDonald

Thanks for the question, sridhar kumar .

Asked: October 07, 2016 - 7:08 am UTC

Last updated: October 08, 2016 - 1:32 am UTC

Version: 11.2.0.4.0

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Hi Team,

I want a customized query which should give me which SQL statement is taking more amount of undo tablespace size with all the details. Request you to please help me on this.

Regards,
Sridhar

and Connor said...

For active transactions, you can look at the USED_UBLK, USED_UREC columns in v$transaction.

For SQL statements, you can get an approximation of number of rows changed (and hence likely undo consumed) via V$SQL.ROWS_PROCESSED for insert/update/del/merge commands.

And at session level, you use the 'undo change vector size' statistic from v$sesstat to pick out those sessions that have consumed the most undo

Hope this helps.

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Undo query

SRIDHAR KUMAR SAHU, October 08, 2016 - 8:58 am UTC

Thanks connor for answering my question
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