Explanation
* You can take an online tablespace offline so that it is temporarily unavailable for general use. The rest of the database remains open and available for users to access data. Conversely, you can bring an offline tablespace online to make the schema objects within the tablespace available to database users. The database must be open to alter the availability of a tablespace.

DBMS_FGA.add_policy
*The DBMS_FGA package provides fine-grained security functions.
*ADD_POLICY Procedure
This procedure creates an audit policy using the supplied predicate as the audit condition.
Incorrect:
Not C: object_schema
The schema of the object to be audited. (If NULL, the current log-on user schema is assumed.)

* Oracle Database provides a mechanism to make table structure modifications without significantly affecting the availability of the table. The mechanism is called online table redefinition. Redefining tables online provides a substantial increase in availability compared to traditional methods of redefining tables.
*To redefine a table online:
Choose the redefinition method: by key or by rowid
*By key-Select a primary key or pseudo-primary key to use for the redefinition. Pseudo-primary keys are unique keys with all component columns having NOT NULL constraints. For this method, the versions of the tables before and after redefinition should have the same primary key columns.
This is the preferred and default method of redefinition.
*By rowid-Use this method if no key is available. In this method, a hidden column named M_ROW$$ is added to the post-redefined version of the table. It is recommended that this column be dropped or marked as unused after the redefinition is complete. If COMPATIBLE is set to
10.2.0 or higher, the final phase of redefinition automatically sets this column unused. You can then use the ALTER TABLE ... DROP UNUSED COLUMNS statement to drop it.
You cannot use this method on index-organized tables.
Note:
* When you rebuild an index, you use an existing index as the data source. Creating an index in this manner enables you to change storage characteristics or move to a new tablespace. Rebuilding an index based on an existing data source removes intra-block fragmentation. Compared to dropping the index and using the CREATE INDEX statement, re-creating an existing index offers better performance.
Incorrect:
Not E: Edition-based redefinition enables you to upgrade the database component of an application while it is in use, thereby minimizing or eliminating down time.

*A fundamental aspect of the workload repository is that it collects and persists database performance data in a manner that enables historical performance analysis. The mechanism for this is the AWR snapshot. On a periodic basis, AWR takes a "snapshot" of the current statistic values stored in the database instance's memory and persists them to its tables residing in the SYSAUX tablespace.
*AWR is primarily designed to provide input to higherlevel components such as automatic tuning algorithms and advisors, but can also provide a wealth of information for the manual tuning process.