If you do decide to suppress redo logging for certain operations, you would include the
NOLOGGING keyword in the SQL statement for the operation. (Note that prior to
Oracle8, the keyword was UNRECOVERABLE.) If a failure occurred during the operation,
youwou ld need to repeat the operation. For example, youmight build an index
on a table without generating redo information. In the event that a database failure
occurs and the database is recovered, the index will not be re-created because it wasn??™t
logged. You??™d simply execute the script originally intended to create the index again.
Deploying Physical Components | 43
To simplify operations in the event of a failure, we recommend that you always take
a backup after an unlogged operation if you cannot afford to lose the object created
by the operation or youcannot repeat the operation for some reason. In addition to
using the NOLOGGING keyword in certain commands, you can also mark a table
or an entire tablespace with the NOLOGGING attribute. This will suppress redo
information for all applicable operations on the table or for all tables in the
tablespace.
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