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ORA-01555 Using Automatic Undo Management - Causes and Solutions (Doc ID 269814.1)

Last updated on FEBRUARY 19, 2019

Applies to:

Oracle Database - Enterprise Edition - Version 9.0.1.0 and later
Oracle Database Exadata Cloud Machine - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Cloud Exadata Service - Version N/A and later
Oracle Database Exadata Express Cloud Service - Version N/A and later
Information in this document applies to any platform.

Purpose

This article discusses the circumstances under which a query can return the ORA-01555 "snapshot too old (rollback segment too small)" error when using the Automatic Undo Management (hereafter called AUM) feature and also possible solutions to this error.

Scope

This document is intended for Oracle DBAs experiencing the ORA-01555 error.

Details

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