4.312 DBA_HIST_DB_CACHE_ADVICE

DBA_HIST_DB_CACHE_ADVICE displays historical predictions of the number of physical reads for the cache size corresponding to each row.

This view contains snapshots of V$DB_CACHE_ADVICE.

Column	Datatype	NULL	Description
SNAP_ID	NUMBER	NOT NULL	Unique snapshot ID
DBID	NUMBER	NOT NULL	Database ID for the snapshot
INSTANCE_NUMBER	NUMBER	NOT NULL	Instance number for the snapshot
BPID	NUMBER	NOT NULL	Buffer Pool identifier (ranges from 1 to 8)
BUFFERS_FOR_ESTIMATE	NUMBER	NOT NULL	Cache size for prediction (in terms of buffers)
NAME	VARCHAR2(20)		Buffer pool name
BLOCK_SIZE	NUMBER		Block size in bytes for buffers in the pool (the standard block size, the power of 2 nonstandard block sizes, 2048, 4096, 8192, 16384, or 32768)
ADVICE_STATUS	VARCHAR2(3)		Status of the advisory: ON - Currently running OFF - Disabled (the estimates are historical and calculated when last enabled)
SIZE_FOR_ESTIMATE	NUMBER		Cache size for prediction (in megabytes)
SIZE_FACTOR	NUMBER		Size factor with respect to the current cache size
PHYSICAL_READS	NUMBER		Physical reads for the cache size
BASE_PHYSICAL_READS	NUMBER		Base physical reads for the cache size
ACTUAL_PHYSICAL_READS	NUMBER		Actual physical reads for the cache size
ESTD_PHYSICAL_READ_TIME	NUMBER		Estimated physical read time for the cache size
CON_DBID	NUMBER		The database ID of the PDB for the sampled session
CON_ID	NUMBER		The ID of the container that CON_DBID identifies. Possible values include: 0: This value is used for rows containing data that pertain to the entire CDB. This value is also used for rows in non-CDBs. 1: This value is used for rows containing data that pertain to only the root n: Where n is the applicable container ID for the rows containing data

See Also:

"V$DB_CACHE_ADVICE"