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Resolving ORA-30036 Error: Unable to Extend Segment by String in Undo Tablespace (KBA1834)


The page describes how to best mask an Oracle database table and how to avoid and resolve ORA-30036: unable to extend segment by string in undo tablespace "tablespace". 

At a Glance  

ORA Error: ORA-30036: unable to extend segment by string in undo tablespace "tablespace"
Affects ME versions: This issue affects all Masking Versions: 4.x, 5.0, 5.1, 5.2, and 5.3.
Root Cause: The specified tablespace has no more space available to perform UPDATE or INSERT.
Solution: The UNDO tablespace is too small. The action here is to either:
  1. Set autoextend on the UNDO tablespace, or
  2. Manually create a new bigger UNDO tablespace and use this one. 

For details, contact your DBA for assistance. 


ORA-30036 error is reported when the current Undo tablespace has no more free space available for the active transactions. This issue has to be resolved in order to proceed. 


To troubleshoot this error, use 'sqlplus' on a terminal and: 

  • Check free space in the UNDO tablespace.
  • Check if the specified UNDO tablespace in autoextensible.
  • Check unexpired extents. 
  • Check the status of the UNDO extents. 

For details on the steps above please see Oracle Doc ID 460481.1.


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