One advantage to using export and import is that a database power user may be able to manage
their own backups and recoveries, especially in a development environment. Also, a binary file
generated by export is typically readable across Oracle versions, making a transfer of a small set
of tables from an older version to a newer version of Oracle fairly straightforward.
Export and import are inherently ???point in time??? backups and therefore are not the most
robust backup and recovery solutions if the data is volatile.
In Oracle 10g, Oracle Data Pump takes import and export operations to a new performance
level. Exports to an external data source can be up to two times faster, and an import operation
can be up to 45 times faster because Data Pump Import uses direct path loading, unlike traditional
import. In addition, an export from the source database can be simultaneously imported into the
target database without an intermediate dump file, saving time and administrative effort. Oracle
Data Pump is implemented using the DBMS_DATAPUMP package with the expdb and impdb
commands and includes numerous other manageability features, such as fine-grained object
selection. More information on Oracle Data Pump is provided in Chapter 17.
Offline Backups
One of the ways to make a physical backup of the database is to perform an offline backup. To
perform an offline backup, the database is shut down and all database-related files, including
datafiles, control files, SPFILEs, password files, and so forth, are copied to a second location.
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