How does one backup a database using the export utility? (for DBA

How does one backup a database using the export utility?
(for DBA
by

1 Answer

Answer :

Oracle exports are "logical" database backups (not physical) as they
extract data and logical definitions from the database into a file. Other
backup strategies normally back-up the physical data files.
One of the advantages of exports is that one can selectively re-import
tables, however one cannot roll-forward from an restored export file.
To completely restore a database from an export file one practically
needs to recreate the entire database.
Always do full system level exports (FULL=YES). Full exports include
more information about the database in the export file than user level
exports.
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