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Oracle Database Migration Assistant for Unicode:
Near-Zero Downtime Migration Model

Updated: October 2011


For mission-critical production systems, limiting the migration downtime window requirement to a minimum is always a top consideration. The DMU presentation at Oracle OpenWorld 2011 – "Near-Zero Downtime Unicode Migration with Oracle Database Migration Assistant for Unicode" – introduces a mechanism to achieve near-zero downtime migration by leveraging Oracle DMU and Streams technology. Below are the links to the presentation and a separate step-by-step document that illustrates the procedure in more details along with proof-of-concept sample scripts.
Presentation Files
  Presentation 1 (PDF)
  Presentation 2 (PDF)
Step-by-Step Document
  Near-Zero Downtime DB Character Set Migration - Proof of Concept (PDF)
Sample Scripts
  Near-Zero Downtime DB Character Set Migration - Scripts (tar+gzip)


Oracle has a very active research organization (Oracle Labs) that is charged to 'Identify, explore, and transfer new technologies that have the potential to substantially improve Oracle's business'. One part of the organization is the External Research Office (ERO). The ERO is charged to ' ... invest in research collaborations that fit Oracle's long-term strategic goals. These collaborations are between university researchers and engineers/researchers throughout Oracle's various organizations'. The ERO webpage lists numerous current and past collaborations. Oracle provides funds and direct interactions with highly experienced developers.

If you are interested in the ERO program please contact Steve Jeffreys at

If you would like to explore opportunities for a research collaboration with the database team please contact Dieter Gawlick at

or Garret Swart at
Oracle Database Cloud