Oracle Database 12c: Installation and Administration — Question 141

Which three are true about the default database buffer cache? (Choose three.)

Answer options

• A. Buffers containing block images may be selected for reuse based only on a Least Recently Used (LRU) algorithm.
• B. It is in the fixed area of the SGA.
• C. Its buffers can contain data block images for blocks that have a corresponding image in a data file.
• D. Buffers containing block images may be selected for reuse based only on a touch count algorithm.
• E. It can contain block images only for database blocks whose block size is equal to the buffer size.
• F. The keep and recycle cache memory is sub-allocated from memory allocated to the default buffer cache.
• G. Its buffers can contain data block images for blocks that have no corresponding image in a data file.

Correct answer: C, E, G

Explanation

The correct options, C, E, and G, accurately describe characteristics of the default database buffer cache. C states that buffers can hold data block images corresponding to blocks in a data file, while E emphasizes that the block size must equal the buffer size. G highlights the unique capability of storing block images even when there is no corresponding image in a data file. Options A, D, and F are incorrect as they reference algorithms or conditions that do not apply to the default buffer cache's operations.