5.292 DBA_ROLLBACK_SEGS

DBA_ROLLBACK_SEGS describes rollback segments.

Column Datatype NULL Description

SEGMENT_NAME

VARCHAR2(30)

NOT NULL

Name of the rollback segment

OWNER

VARCHAR2(6)

Owner of the rollback segment:

  • PUBLIC

  • SYS

TABLESPACE_NAME

VARCHAR2(30)

NOT NULL

Name of the tablespace containing the rollback segment

SEGMENT_ID

NUMBER

NOT NULL

ID number of the rollback segment

FILE_ID

NUMBER

NOT NULL

File identifier number of the file containing the segment head

BLOCK_ID

NUMBER

NOT NULL

ID number of the block containing the segment header

INITIAL_EXTENT

NUMBER

Initial extent size in bytes

NEXT_EXTENT

NUMBER

Secondary extent size in bytes

MIN_EXTENTS

NUMBER

NOT NULL

Minimum number of extents

MAX_EXTENTS

NUMBER

NOT NULL

Maximum number of extent

PCT_INCREASE

NUMBER

Percent increase for extent size

STATUS

VARCHAR2(16)

Rollback segment status:

  • OFFLINE

  • ONLINE

  • NEEDS RECOVERY

  • PARTLY AVAILABLE

  • UNDEFINED

INSTANCE_NUM

VARCHAR2(40)

Rollback segment owning Oracle Real Application Clusters instance number

RELATIVE_FNO

NUMBER

NOT NULL

Relative file number of the segment header