Distributed Database Question Bank with Answers 04

Question:

When and why is replication favorable in a distributed database?

Answer:

Replication will speed up data access for data that is seldom updated.

Replication is favorable when the update frequency is low since the DDBMS must otherwise use a lot of resources to keep the different copies of the database up-to-date. For example, in a replicated database this would mean that all updates to the one replicated table would have to be propagated to each distributed node. On the other hand replication is very good for read-only databases since then only local accesses would be needed.

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