Unformatted text preview: CREATE TABLE ... AS SELECT.
A: UPDATE SQL statement cannot use the NOLOGGING mode to reduce redo operations:
changes will be written into redo log files any way.
D: Conventional path INSERT will update redo log files. Only direct load path can avoid redo
log files modification.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 873-876.
Chapter 18: Tuning Memory and Operating System Use
Which two statements about database blocks are true? (Choose two)
A. DSS environment prefer a large block size
B. Small block sizes result in more block
C. Random access to large objects favours a large block size.
D. You can reduce the number of block visits by packing rows as closely as possible into blocks.
E. To change the database block size, you must shut down the instance and perform a STARTUP
RESETLOGS after you make the change.
Answer: A, D
The key feature of a decision support system is fast access to large amounts of data, so DSS
environment prefer a large database block size. Also remember that you can reduce the number
of block visits by packing rows as closely as possible into blocks, so Oracle will need less table
scans to retrieve all needed blocks.
B: Small block sizes will not result in more block contention.
C: Random access to large objects will work better with small block size. It happens often in
OLTP systems. For full scans large block size is more preferable (DSS systems).
E: To change the database block size, you must rebuild database. Shutdown the instance and
STARTUP with RESETLOGS option will not change database block size.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 793-796.
Chapter 17: Tuning Database Applications
The ORDERS table has millions of rows and is accessed very often with an index
(ORDID_NDX) on a primary key (ORD_ID). Where should ORDERS and ORDID_NDX
A. Same tablespace
Actualtests.com - The Power of Knowing 1Z0-024
B. Different tablespace on th...
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- Fall '09
- Oracle Database, Jason S. Couchman, DBA Certification Exam, Certification Exam Guide