DBA_SEGMENTS_OLD lists information about storage allocated for all database segments.
| Column | Datatype | NULL | Description | 
|---|---|---|---|
OWNER | 
VARCHAR2(30) | 
Username of the segment owner | |
SEGMENT_NAME | 
VARCHAR2(81) | 
Name, if any, of the segment | |
PARTITION_NAME | 
VARCHAR2(30) | 
Name of the partition | |
SEGMENT_TYPE | 
VARCHAR2(18) | 
Type of segment: INDEX PARTITION, TABLE PARTITION, TABLE, CLUSTER, INDEX, ROLLBACK, DEFERRED ROLLBACK, TEMPORARY, CACHE, LOBSEGMENT and LOBINDEX | 
|
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 | |
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 the 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) | 
Buffer pool for the object |