你可能感興趣的試題

You have executed this command to change the size of the database buffer cache： SQL> ALTER SYSTEM SET DB_CACHE_SIZE=2516582； System altered.
To verify the change in size， you executed this command： SQL> SHOW PARAMETER DB_CACHE_SIZE NAME TYPE VALUE
------------------- ----------- ------------------
db_cache_size big integer 4194304 （4M）
Why is the value set to 4194304 and not to 2516582（）

A.because 4194304 is the granule size
B.because 4194304 is the standard block size
C.because 4194304 is the largest nonstandard block size defined in the database
D.because 4194304 is the total size of data already available in the database buffer cache

單項選擇題

Which is the correct description of a pinned buffer in the database buffer cache（）

A.The buffer is currently being accessed.
B.The buffer is empty and has not been used.
C.The contents of the buffer have changed and must be flushed to the disk by the DBWn process.
D.The buffer is a candidate for immediate aging out and its contents are synchronized with the block contents on the disk.