V$IM_SEGMENTS

V$IM_SEGMENTS presents information about all the in-memory segments in the database.

Only segments that have an in-memory representation are displayed. If a segment is marked for the In-Memory Column Store (IM column store) but is not populated, no corresponding row for that segment is displayed in this view.

Column Datatype Description

OWNER

VARCHAR2(128)

User name of the segment owner

SEGMENT_NAME

VARCHAR2(128)

Name of the segment, if any

PARTITION_NAME

VARCHAR2(128)

Object partition name (set to NULL for non-partitioned objects)

SEGMENT_TYPE

VARCHAR2(18)

Type of segment:

  • TABLE

  • TABLE PARTITION

  • TABLE SUBPARTION

TABLESPACE_NAME

VARCHAR2(30)

Name of the tablespace containing the segment

INMEMORY_SIZE

NUMBER

Size of the in-memory version of the segment, in bytes

BYTES

NUMBER

Total size of the on-disk segment, in bytes

BYTES_NOT_POPULATED

NUMBER

Size of the portion of the on-disk segment that is not populated in memory, in bytes

POPULATE_STATUS

VARCHAR2(9)

Status of segment population:

  • STARTED

  • COMPLETED

  • FAILED

INMEMORY_PRIORITY

VARCHAR2(8)

Indicates the priority for IM column store population:

  • LOW

  • MEDIUM

  • HIGH

  • CRITICAL

  • NONE

INMEMORY_DISTRIBUTE

VARCHAR2(15)

Indicates how the IM column store is distributed in an Oracle Real Application Clusters (Oracle RAC) environment:

  • AUTO

  • BY ROWID RANGE

  • BY PARTITION

  • BY SUBPARTITION

INMEMORY_DUPLICATE

VARCHAR2(13)

Indicates the duplicate setting for the IM column store in an Oracle RAC environment:

  • NO DUPLICATE

  • DUPLICATE

  • DUPLICATE ALL

INMEMORY_COMPRESSION

VARCHAR2(17)

Compression level for the IM column store:

  • NO MEMCOMPRESS

  • FOR DML

  • FOR QUERY [ LOW | HIGH ]

  • FOR CAPACITY [ LOW | HIGH ]

CON_ID

NUMBER

The ID of the container to which the data pertains. Possible values include:

  • 0: This value is used for rows containing data that pertain to the entire multitenant container database (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

Note:

This view is available starting with Oracle Database 12c Release 1 (12.1.0.2).

See Also: