QUESTION 151
You want to use RMAN to create compressed backups.
Which statement is true about the compression algorithms that RMAN can use?
A. The BZIP2 compression algorithm consumes more CPU resources than the ZLIB compression algorithm.
B. The ZLIB compression algorithm consumes more CPU resources than the BZIP2 compression algorithm.
C. The ZLIB compression algorithm provides maximum compression and produces smaller backups than the
BZIP2 compression algorithm.
D. Only the BZIP2 compression algorithm can be used tomake compressed backups to disk.
Answer: A
同53题:http://blog.csdn.net/rlhua/article/details/14093639
Explanation/Reference:
Section: Backup, Recovery & Recovery Manager (RMAN)
The BZIP2 compression algorithm consumes more CPU resources than the ZLIB compression algorithm. The
BZIP2 compression algorithm provides for optimum compression, but tends to use more CPU resources than
the ZLIB compression algorithm. The ZLIB compression algorithm is optimized for performance and uses less
CPU resources. You should note that the COMPATIBLE initialization parameter must be set to 11.0.0 or higher
to use the ZLIB compression algorithm.
The option that states the ZLIB compression algorithm consumes more CPU resources than the BZIP2
compression algorithm is incorrect. The BZIP2 compression algorithm consumes more CPU resources. The
option that states the ZLIB compression algorithm provides maximum compression and produces smaller
backups than the BZIP2 compression algorithm is incorrect. The BZIP2 compression algorithm provides
maximum compression and produces smaller backups than the ZLIB compression algorithm.
The option that states only the BZIP2 compression algorithm can be used to make compressed backups to disk
is incorrect. The ZLIB compression algorithm can also be used to make compressed backups to disk.