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Oracle® Database Reference
12c Release 1 (12.1)

E17615-23
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V$BH

V$BH displays the status and number of pings for every buffer in the SGA. This is a Real Application Clusters view.

Column Datatype Description
FILE# NUMBER Data file identifier number (to find the file name, query DBA_DATA_FILES or V$DBFILE)
BLOCK# NUMBER Block number
CLASS# NUMBER Class number
STATUS VARCHAR2(10) Status of the buffer:
  • free - Not currently in use

  • xcur - Exclusive

  • scur - Shared current

  • cr - Consistent read

  • read - Being read from disk

  • mrec - In media recovery mode

  • irec - In instance recovery mode

XNC NUMBER This column is obsolete. Its value is hard-coded to 0.
FORCED_READS NUMBER This column is obsolete. Its value is hard-coded to 0.
FORCED_WRITES NUMBER This column is obsolete. Its value is hard-coded to 0.
LOCK_ELEMENT_ADDR RAW(4 | 8) Address of the lock element that contains the PCM lock that is covering the buffer. If more than one buffer has the same address, then these buffers are covered by the same PCM lock.
LOCK_ELEMENT_NAME NUMBER The address of the lock element that contains the PCM lock that is covering the buffer. If more than one buffer has the same address, then these buffers are covered by the same PCM lock.
LOCK_ELEMENT_CLASS NUMBER The address of the lock element that contains the PCM lock that is covering the buffer. If more than one buffer has the same address, then these buffers are covered by the same PCM lock.
DIRTY VARCHAR2(1) Y - block modified
TEMP VARCHAR2(1) Y - temporary block
PING VARCHAR2(1) Y - block pinged
STALE VARCHAR2(1) Y - block is stale
DIRECT VARCHAR2(1) Y - direct block
NEW CHAR(1) Always set to N. This column is obsolete and maintained for backward compatibility.
OBJD NUMBER Database object number of the block that the buffer represents
TS# NUMBER Tablespace number of block
LOBID NUMBER If the buffer belongs to a SecureFiles object, the value in this column is the unique identifier for the SecureFiles object. For other buffer types, the value in this column is meaningless.
CACHEHINT NUMBER Numeric representation of the values in the FLASH_CACHE and CELL_FLASH_CACHE columns. See the descriptions and possible values for the FLASH_CACHE and CELL_FLASH_CACHE columns in this view.
FLASH_CACHE VARCHAR2(7) Database Smart Flash Cache hint to be used for segment blocks:
  • DEFAULT

  • KEEP

  • NONE

Solaris and Oracle Linux functionality only.

CELL_FLASH_CACHE VARCHAR2(7) Cell flash cache hint to be used for segment blocks:
  • DEFAULT

  • KEEP

  • NONE

See Also: Oracle Exadata Storage Server Software documentation for more information

CON_ID NUMBER The ID of the container to which the data pertains. 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