What action is required for dependent objects when you …

You need to perform an online table redefinition of an existing SALES table to partition it into two tablespaces
TBS1 and TBS2. The SALES table has a materialized view, materialized log, indexes, referential integrity
constraint, and triggers with the PRECEDES clause existing on it.
What action is required for dependent objects when you perform online table redefinition?

You need to perform an online table redefinition of an existing SALES table to partition it into two tablespaces
TBS1 and TBS2. The SALES table has a materialized view, materialized log, indexes, referential integrity
constraint, and triggers with the PRECEDES clause existing on it.
What action is required for dependent objects when you perform online table redefinition?

A.
The dependent materialized view should have a complete refresh performed after the online table
redefinition process.

B.
Triggers with the PRECEDES clause should be disabled before the online table redefinition process.

C.
Referential integrity constraints must be manually enabled after the online table redefinition process.

D.
The materialized log should be dropped before the online table redefinition process.

Explanation:
When performing the online table redefinition, you will:
Copy dependent objects (such as triggers, indexes, materialized view logs, grants, and constraints) and
statistics from the table being redefined to the interim table, using one of the following two methods. Method 1
is the preferred method because it is more automatic, but there may be times that you would choose to use
method 2. Method 1 also enables you to copy table statistics to the interim table.
Results of the Redefinition Process (link)
The following are the end results of the redefinition process:
The original table is redefined with the columns, indexes, constraints, grants, triggers, and statistics of the
interim table.
Dependent objects that were registered, either explicitly using REGISTER_DEPENDENT_OBJECT or implicitly
using COPY_TABLE_DEPENDENTS, are renamed automatically so that dependent object names on the
redefined table are the same as before redefinition.Note:
If no registration is done or no automatic copying is done, then you must manually rename the dependent
objects.
The referential constraints involving the interim table now involve the redefined table and are
enabled. Any indexes, triggers, materialized view logs, grants, and constraints defined on the original table
(prior to redefinition) are transferred to the interim table and are dropped when the user drops the interim table.
Any referential constraints involving the original table before the redefinition now involve the interim table and
are disabled.
Some PL/SQL objects, views, synonyms, and other table-dependent objects may become invalidated. Only
those objects that depend on elements of the table that were changed are invalidated. For example, if a PL/
SQL procedure queries only columns of the redefined table that were unchanged by the redefinition, the
procedure remains valid. See “Managing Object Dependencies” for more information about schema object
dependencies.
Restrictions for Online Redefinition of Tables (link)
After redefining a table that has a materialized view log, the subsequent refresh of any dependent materialized
view must be a complete refresh.



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