IF: How to monitor Undo Tablespace Usage and the Free Space

(Doc ID 1951400.1)

Last updated on APRIL 10, 2018

Applies to:

Oracle Database - Enterprise Edition - Version 9.2.0.1 and later
Information in this document applies to any platform.
***Checked for relevance on 21-Jul-2017***

Symptoms

This document provides the various queries that can be used to monitor Undo space usage.

The Undo Space once allocated wont be deallocated to the OS, by default. But the space can be reused by other transactions once the UNDO_RETENION (or TUNED_UNDORETENTION period) is met.

Changes

Cause

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