Exhibit
Examine the SQL statement used to create the EMP table.
You need to shrink the EMP table segment.
Which SQL statement would you execute as a prerequisite before you execute the ALTER TABLE emp SHRINK SPACE; command?
A.
ALTER TABLESPACE emp OFFLINE;
B.
ALTER TABLESPACE emp READ ONLY;
C.
ALTER TABLE emp DEALLOCATE UNUSED;
D.
ALTER TABLE emp ENABLE ROW MOVEMENT;
E.
ALTER TABLE emp DISABLE ALL TRIGGERS;
F ALTER TABLE emp ENABLE NOVALIDATE CONSTRAINT emp_last_name_nn;
Explanation:
Segment shrink reclaims unused space both above and below the high water mark. In contrast, space deallocation reclaims unused space only above the high water mark. In shrink operations, by default, the database compacts the segment, adjusts the high water mark, and releases the reclaimed space.
Segment shrink requires that rows be moved to new locations. Therefore, you must first
enable row movement in the object you want to shrink and disable any rowid-based triggers defined on the object.REF: Oracle(r) 10g Administrator Guide , 14-48