The extent of the data divergence and potential data loss resulting from the divergence
is a very important consideration in configuring asynchronous replication. In
addition, asynchronous replication allows the primary site to function when the network
or the secondary site is down, while synchronous replication requires that the
secondary site be available. Asynchronous replication adds overhead to transactions
at the primary site, so once again, you??™ll need to carefully consider throughput
requirements and perform appropriate testing. Typically, asynchronous replication
adds less overhead than synchronous replication, since the replication of changes can
be efficiently batched to the secondary site. However, asynchronous replication will
still add some overhead to the operation of the primary site, so youshou ld consider
and test the effect of both types of replication on your database environment.
Old-Fashioned Data Redundancy
You can also achieve data redundancy using Oracle??™s standard utilities. Historically,
one of the most common backup methods for Oracle was simply to export the contents
of the database into a file using the Oracle Export utility.
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