You observed that some of the queries are performing poorly on the SALES_RECORDS table in your database.
On further investigation, you find that at the end of each day the contents of the
SALES_RECORDS table are transferred to the SALES table and deleted from the
SALES_RECORDS table. The deleted operations cause the table to be sparsely populated.
The SALES_RECORDS table has Automatic Segment Space Management (ASSM) and row
movement enabled. The table is accessible in 24×7 mode.
What is the most efficient method to improve the performance?
A.
Perform EXPORT, DROP, and IMPORT operations on the SALES_RECORDS table
sequentially.
B.
Shrink the SALES_RECORDS table by using the ALTER TABLE…SHRINK SPACE command.
C.
Move the SALES_RECORDS table to a different location by using the ALTER TABLE…MOVE
command.
D.
Deallocate the space in the SALES_RECORDS table by using the ALTER
TABLE…DEALLOCATE UNUSED command.
A is wrong. not online operation
B is right.
C is wrong. move cause outage
D is wrong. no such syntax
B is right.