DBA_SEGMENTS

DBA_SEGMENTS describes the storage allocated for all segments in the database.

Related View

USER_SEGMENTS describes the storage allocated for the segments owned by the current user's objects. This view does not display the OWNER, HEADER_FILE, HEADER_BLOCK, or RELATIVE_FNO columns.

Column	Datatype	Description
`OWNER`	`VARCHAR2(30)`	Username of the segment owner
`SEGMENT_NAME`	`VARCHAR2(81)`	Name, if any, of the segment
`PARTITION_NAME`	`VARCHAR2(30)`	Object Partition Name (Set to `NULL` for non-partitioned objects)
`SEGMENT_TYPE`	`VARCHAR2(18)`	Type of segment: `NESTED TABLE` `TABLE` `TABLE PARTITION` `CLUSTER` `LOBINDEX` `INDEX` `INDEX PARTITION` `LOBSEGMENT` `TABLE SUBPARTITION` `INDEX SUBPARTITION` `LOB PARTITION` `LOB SUBPARTITION` `ROLLBACK` `TYPE2 UNDO` `DEFERRED ROLLBACK` `TEMPORARY` `CACHE` `SPACE HEADER` `UNDEFINED`
`SEGMENT_SUBTYPE`	`VARCHAR2(10)`	Subtype of LOB segment: `SECUREFILE`, `ASSM`, `MSSM`, and `NULL`
`TABLESPACE_NAME`	`VARCHAR2(30)`	Name of the tablespace containing the segment
`HEADER_FILE`	`NUMBER`	ID of the file containing the segment header
`HEADER_BLOCK`	`NUMBER`	ID of the block containing the segment header
`BYTES`	`NUMBER`	Size, in bytes, of the segment
`BLOCKS`	`NUMBER`	Size, in Oracle blocks, of the segment
`EXTENTS`	`NUMBER`	Number of extents allocated to the segment
`INITIAL_EXTENT`	`NUMBER`	Size in bytes requested for the initial extent of the segment at create time. (Oracle rounds the extent size to multiples of 5 blocks if the requested size is greater than 5 blocks.)
`NEXT_EXTENT`	`NUMBER`	Size in bytes of the next extent to be allocated to the segment
`MIN_EXTENTS`	`NUMBER`	Minimum number of extents allowed in the segment
`MAX_EXTENTS`	`NUMBER`	Maximum number of extents allowed in the segment
`MAX_SIZE`	`NUMBER`	Maximum number of blocks allowed in the segment
`RETENTION`	`VARCHAR2(7)`	Retention option for `SECUREFILE` segment
`MINRETENTION`	`NUMBER`	Minimum retention duration for `SECUREFILE` segment
`PCT_INCREASE`	`NUMBER`	Percent by which to increase the size of the next extent to be allocated
`FREELISTS`	`NUMBER`	Number of process freelists allocated to this segment
`FREELIST_GROUPS`	`NUMBER`	Number of freelist groups allocated to this segment
`RELATIVE_FNO`	`NUMBER`	Relative file number of the segment header
`BUFFER_POOL`	`VARCHAR2(7)`	Default buffer pool for the object