8.201 V$EQ_MESSAGE_CACHE

V$EQ_MESSAGE_CACHE provides performance statistics of the message cache for Transactional Event Queues (TEQs) at the event stream partition level in the instance.

Column Datatype Description

QUEUE_ID

NUMBER

Queue ID

EVENT_STREAM_ID

NUMBER

Event stream ID

PRIORITY

NUMBER

Priority of the event stream partition for dequeue, range 0 - 9

EVENT_STREAM_PARTITION_ID

NUMBER

Event stream partition ID

PARTITION_ID

NUMBER

Queue partition ID

MAX_MSGS

NUMBER

Maximum number of messages for the event stream partition

ENQUEUED_MSGS

NUMBER

Number of messages enqueued for the event stream partition

MSGS_MADE_EXPIRED

NUMBER

Number of messages made expired

CHUNK_SIZE

NUMBER

The size of the memory chunk for storing messages

NUM_CHUNKS

NUMBER

Number of chunks for the event stream partition

NUM_FREE_CHUNKS

NUMBER

Number of free chunks for the event stream partition

USED_MEMORY_SIZE

NUMBER

Total estimated size of memory in use (in bytes) for the event stream partition

STATE

VARCHAR2(13)

Event stream partition state. Possible values:

  • CACHED (in memory)

  • UNCACHED (on disk)

  • UNCACHED_FREE

  • CACHED_FREE

  • UNKNOWN

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 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 21c.

See Also:

Oracle Database Advanced Queuing User's Guide for more information about Oracle Transactional Event Queues and Advanced Queuing