Which technique will move the table and indexes while m…

Your are the DBA supporting an Oracle 11g Release 2 database and wish to move a table containing
several DATE, CHAR, VARCHAR2, and NUMBER data types, and the table’s indexes, to another
tablespace.
The table does not have a primary key and is used by an OLTP application.
Which technique will move the table and indexes while maintaining the highest level of availability to the
application?

Your are the DBA supporting an Oracle 11g Release 2 database and wish to move a table containing
several DATE, CHAR, VARCHAR2, and NUMBER data types, and the table’s indexes, to another
tablespace.
The table does not have a primary key and is used by an OLTP application.
Which technique will move the table and indexes while maintaining the highest level of availability to the
application?

A.
Oracle Data Pump.

B.
An ALTER TABLE MOVE to move the table and ALTER INDEX REBUILD to move the indexes.

C.
An ALTER TABLE MOVE to move the table and ALTER INDEX REBUILD ONLINE to move the
indexes.

D.
Online Table Redefinition.

E.
Edition-Based Table Redefinition.

Explanation:
* 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 ofredefining 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.



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