Skip Headers

Oracle® Database Reference 10g Release 2 (10.2) Part Number B14237-02 |
Home | Book List | Contents | Index | Master Index | Feedback

Previous | Next
| View PDF

# 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` |  | Unique snapshot ID
`DBID` | `NUMBER` |  | Database ID for the snapshot
`INSTANCE_NUMBER` | `NUMBER` |  | Instance number for the snapshot
`BPID` | `NUMBER` |  | Buffer Pool identifier (ranges from 1 to 8)
`BUFFERS_FOR_ESTIMATE` | `NUMBER` |  | 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 non-standard 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