DBA_HIST_ROWCACHE_SUMMARY

DBA_HIST_ROWCACHE_SUMMARY displays historical summary statistics for data dictionary activity. This view contains snapshots of V$ROWCACHE.

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
`PARAMETER`	`VARCHAR2(32)`	`NOT NULL`	Name of the initialization parameter that determines the number of entries in the data dictionary cache
`TOTAL_USAGE`	`NUMBER`		Sum of the total number of entries in the cache
`USAGE`	`NUMBER`		Number of cache entries that contain valid data
`GETS`	`NUMBER`		Total number of requests for information on the data object
`GETMISSES`	`NUMBER`		Number of data requests resulting in cache misses
`SCANS`	`NUMBER`		Number of scan requests
`SCANMISSES`	`NUMBER`		Number of times a scan failed to find the data in the cache
`SCANCOMPLETES`	`NUMBER`		For a list of subordinate entries, the number of times the list was scanned completely
`MODIFICATIONS`	`NUMBER`		Number of inserts, updates, and deletions
`FLUSHES`	`NUMBER`		Number of times flushed to disk
`DLM_REQUESTS`	`NUMBER`		Number of DLM requests
`DLM_CONFLICTS`	`NUMBER`		Number of DLM conflicts
`DLM_RELEASES`	`NUMBER`		Number of DLM releases
`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