4.249 DBA_EXTENTS

DBA_EXTENTS describes the extents comprising the segments in all tablespaces in the database.

Note that if a data file (or entire tablespace) is offline in a locally managed tablespace, you will not see any extent information. If an object has extents in an online file of the tablespace, you will see extent information about the offline data file. However, if the object is entirely in the offline file, a query of this view will not return any records.

Related View

USER_EXTENTS describes the extents comprising the segments owned by the current user's objects. This view does not display the OWNER, FILE_ID, BLOCK_ID, or RELATIVE_FNO columns.

Column Datatype NULL Description

OWNER

VARCHAR2(128)

Owner of the segment associated with the extent

SEGMENT_NAME

VARCHAR2(128)

Name of the segment associated with the extent

PARTITION_NAME

VARCHAR2(128)

Object Partition Name (Set to NULL for nonpartitioned objects)

SEGMENT_TYPE

VARCHAR2(18)

Type of the segment: INDEX PARTITION, TABLE PARTITION

TABLESPACE_NAME

VARCHAR2(30)

Name of the tablespace containing the extent

EXTENT_ID

NUMBER

Extent number in the segment

FILE_ID

NUMBER

File identifier number of the file containing the extent

BLOCK_ID

NUMBER

Starting block number of the extent

BYTES

NUMBER

Size of the extent in bytes

BLOCKS

NUMBER

Size of the extent in Oracle blocks

RELATIVE_FNO

NUMBER

Relative file number of the first extent block

See Also:

"USER_EXTENTS"