8.69 V$MAP_FILE_EXTENT

V$MAP_FILE_EXTENT displays a list of all file extent mapping structures in the shared memory of the instance.

Column Datatype Description

FILE_MAP_IDX

NUMBER

File index (corresponds to FILE_MAP_IDX in V$MAP_FILE)

EXT_NUM

NUMBER

File extent number

EXT_ELEM_OFF

NUMBER

Element offset in HKB

EXT_SIZE

NUMBER

File extent size in HKB

EXT_FILE_OFF

NUMBER

File Offset in HKB

EXT_TYPE

VARCHAR2(6)

File Extent Type:

  • DATA

  • PARITY

  • NONE

ELEM_IDX

NUMBER

Index in V$MAP_ELEMENT corresponding to the element where the file extent resides

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