Static Data Dictionary Views, 153 of 452

DBA_EXTENTS

DBA_EXTENTS describes the extents comprising all segments in the database.

Related view:

USER_EXTENTS describes extents in segments associated with objects owned by the current user. This view does not display the OWNER, FILE_ID, BLOCK_ID, or RELATIVE_FNO columns.

Column Datatype NULL Description

OWNER

VARCHAR2(30)

Owner of the segment associated with the extent

SEGMENT_NAME

VARCHAR2(81)

Name of the segment associated with the extent

SEGMENT_TYPE

VARCHAR2(17)

Type of the segment: INDEX PARTITION, TABLE PARTITION

TABLESPACE_NAME

VARCHAR2(30)

Name of the tablespace containing the extent

EXTENT_ID

NUMBER

NOT NULL

Extent number in the segment

FILE_ID

NUMBER

NOT NULL

Name of the file containing the extent

BLOCK_ID

NUMBER

NOT NULL

Starting block number of the extent

BYTES

NUMBER

Size of the extent in bytes

BLOCKS

NUMBER

NOT NULL

Size of the extent in Oracle blocks

RELATIVE_FNO

NUMBER

NOT NULL

Relative file number of the first extent block

PARTITION_NAME

VARCHAR2(30)

Object Partition Name (Set to NULL for non-partitioned objects)

Column	Datatype	NULL	Description
`OWNER`	`VARCHAR2(30)`		Owner of the segment associated with the extent
`SEGMENT_NAME`	`VARCHAR2(81)`		Name of the segment associated with the extent
`SEGMENT_TYPE`	`VARCHAR2(17)`		Type of the segment: `INDEX` `PARTITION`, `TABLE` `PARTITION`
`TABLESPACE_NAME`	`VARCHAR2(30)`		Name of the tablespace containing the extent
`EXTENT_ID`	`NUMBER`	`NOT NULL`	Extent number in the segment
`FILE_ID`	`NUMBER`	`NOT NULL`	Name of the file containing the extent
`BLOCK_ID`	`NUMBER`	`NOT NULL`	Starting block number of the extent
`BYTES`	`NUMBER`		Size of the extent in bytes
`BLOCKS`	`NUMBER`	`NOT NULL`	Size of the extent in Oracle blocks
`RELATIVE_FNO`	`NUMBER`	`NOT NULL`	Relative file number of the first extent block
`PARTITION_NAME`	`VARCHAR2(30)`		Object Partition Name (Set to NULL for non-partitioned objects)