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How to Resolve ORA-01562: failed to extend rollback segment number

Found repeated errors in the alert log:
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ORA-01562: failed to extend rollback segment number 96
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It seemed that some transactions were doing DML, but they failed to proceed because of the full of rollback segments. In such situation, you have several options:
  1. If you saw the error repeatedly showed in the alert log, you’d be better to add some space to it. Please manually increase the size of said rollback segment in order to allow transactions to extend the segment automatically.
  2. Killing some of the sessions which were using this rollback segment in order to release the space of rollback segments.
  3. Let users make the decision. That is, if users were able to respond to the database, they can rollback their transactions or insist on waiting for available space.

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