1Z0-054 무료 덤프문제 온라인 액세스

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 24x7 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.

You work as a DBA and have the responsibility of managing a large online transaction processing (OLTP) system. You used three queries to check the database performance as shown in the Exhibit.View the Exhibit and analyze the output.

What conclusion can you draw from this?

• A.There are many full table scans happening.
• B.The DBWn processes are not freeing sufficient buffers to meet the demand.
• C.The data blocks are aging out of the buffer cache very fast.
• D.There are many physical I/Os happening.
• E.There are many cursors trying to access the same data blocks.

While reviewing the Top 5 Timed Events section in the Automatic Workload Repository report, you notice that the db file scattered read and db file sequential read events appear in the list. Which two reasons could have caused these wait events? (Choose two.)

• A.excessive writes due to an aggressive checkpointing policy
• B.SQL statements performing frequent fast full index scans
• C.tablespaces using manual segment space management
• D.SQL statements performing frequent full table scans

You find that in the Top 5 Timed Events section of the Automatic Workload Repository (AWR) report, the wait event buffer busy waits shows significantly high values.The database uses only non-ASSM locally managed tablespaces.On further investigation, you find that the contention is on data blocks.Which option would you consider first to decrease the wait event values on a long-term basis?

• A.decreasing PCTUSED
• B.using automatic segment space management (ASSM)
• C.increasing db_buffer_cache based on the V$DB_CACHE_ADVICE recommendation
• D.increasing the number of DBWn processes
• E.decreasing PCTFREE

On examining the Automatic Workload Repository (AWR) report, you find that log file sync appears among the top 5 wait events.On further investigation, you notice that the average time waited for this event is low, but the number of waits are high.What does this imply?

• A.Redo log buffer size is insufficient.
• B.DBWR is slow.
• C.The application might be committing frequently.
• D.LGWR is slow due to slow I/O.