||Oracle Replication Tips by Burleson
Define the Oracle replication Conflict
Now our replication will function more like a stand-alone database.
If two users modify the same data, the data will be applied in the
order of commits. In our replication, the two transactions will be
applied in the order of the timestamp. This is the most common
conflict resolution method.
There is one caveat to consider with this method. All replication
database servers must be operating on one time standard. If you
have two servers in your replication scheme, one in Virginia and the
other in California, the Virginia server time will be four hours
ahead of the California server.
Normally databases used in a replication environment use a standard
time, either GMT or local time at the company headquarters. It
doesn’t matter as long as they are the same. You can also create
the trigger to compensate for the time differences, but you will not
be able to replicate the trigger. Instead, you will need to create
the trigger at each site, adjusting for the time. Since I live in
Colorado I use Mountain Time, to convert to GMT, I would change the
trigger to convert the time.
If Oracle was unable to resolve the conflict using the latest
timestamp, we could provide an additional resolution method to use.
It’s called the Site Priority method.
This is an
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