4.326 DBA_HIST_IM_SEG_STAT

DBA_HIST_IM_SEG_STAT displays information about historical in-memory segment statistics.

Column Datatype NULL Description

SNAP_ID

NUMBER

NOT NULL

Unique snapshot ID

DBID

NUMBER

NOT NULL

Database ID for the snapshot

INSTANCE_NUMBER

NUMBER

NOT NULL

Instance number for the snapshot

TS#

NUMBER

NOT NULL

Tablespace number

OBJ#

NUMBER

NOT NULL

Dictionary object number

DATAOBJ#

NUMBER

NOT NULL

Data object number

MEMBYTES

NUMBER

Size of in-memory version of the segment in bytes

SCANS

NUMBER

Count of segment statistics

SCANS_DELTA

NUMBER

Delta values for in-memory scans

DB_BLOCK_CHANGES

NUMBER

The total number of changes that were part of an update or delete operation that were made to segment blocks

DB_BLOCK_CHANGES_DELTA

NUMBER

Delta value for database block changes

POPULATE_CUS

NUMBER

Count of compression units (CUs) populated per segment

POPULATE_CUS_DELTA

NUMBER

Delta value for compression unit (CU) populate operations

REPOPULATE_CUS

NUMBER

Count of CUs repopulated per segment

REPOPULATE_CUS_DELTA

NUMBER

Delta value for compression unit (CU) repopulate operations

CON_DBID

NUMBER

The database ID of the PDB for the sampled session

CON_ID

NUMBER

The ID of the container that CON_DBID identifies. Possible values include:

  • 0: This value is used for rows containing data that pertain to the entire CDB. This value is also used for rows in non-CDBs.

  • 1: This value is used for rows containing data that pertain to only the root

  • n: Where n is the applicable container ID for the rows containing data