If a table in the CCTR database is
changed along with a table in the WHSE database, and the network connection between the
databases fails before the table in the WHSE database can be updated, RECO will roll back the
failed transaction.
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38 Oracle Database 11g DBA Handbook
Backup/Recovery Overview
Oracle supports many different forms of backup and recovery. Some of them can be managed at
the user level, such as export and import; most of them are strictly DBA-centric, such as online or
offline backups and using operating system commands or the RMAN utility.
Details for configuring and using these backup and recovery methods can be found in
Chapter 11 and also in Chapter 12.
Export/Import
The export command is a standalone utility on all Oracle hardware and software platforms, and
it??™s started by running the command exp at the operating system command-line prompt or through
the Oracle Enterprise Manager console in a GUI environment. Export is considered a logical
backup, because the underlying storage characteristics of the tables are not recorded, only the
table metadata, user privileges, and table data. Depending on the task at hand, and whether you
have DBA privileges or not, the exp command can either export all tables in the database, all the
tables of one or more users, or a specific set of tables.
For restoring from a database export, the import command, started by running the command
imp, takes a binary format file created by export and imports it into the database with the
assumption that the users in the exported database tables exist in the database where the import
command is performed.
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