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Discuss the Update-anywhere (symmetric replication) ownership in replication

Discuss the Update-anywhere (symmetric replication) ownership in replication

Answers

KELVIN
The update-anywhere model creates a peer-to-peer environment where multiple sites have equal rights to update replicated data. This allows local sites to function autonomously, even when other sites are not available.
Shared ownership can lead to conflict scenarios and the replication architecture has to be able to employ a methodology for conflict detection and resolution. A simple mechanism to detect conflict within a single table is for the source site to send both the old and new values (before- and after-images) for any records that have been updated since the last refresh. At the target site, the replication server can check each record in the target database that has also been updated against these values. However, consideration has to be given to detecting other types of conflict such as violation of referential integrity between two tables. There have been many mechanisms proposed for conflict resolution, but some of the most common are: earliest/latest timestamps, site priority, and holding for manual resolution.
kalvinspartan answered the question on July 4, 2018 at 16:43

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