8.24 V$AQ_MESSAGE_CACHE

V$AQ_MESSAGE_CACHE provides performance statistics of the message cache for sharded queues at the subshard level in the instance.

Note:

AQ sharded queues are deprecated in Oracle Database 21c. Oracle recommends that you instead use Transactional Event Queues (TEQs) for higher throughput and better performance.

Column	Datatype	Description
QUEUE_ID	NUMBER	Queue ID
SHARD_ID	NUMBER	Shard ID
PRIORITY	NUMBER	Priority of the subshard for dequeue, range 0-9
SUBSHARD_ID	NUMBER	Subshard ID in the shard
PARTITION_ID	NUMBER	Partition id for the particular subshard
MAX_MSGS	NUMBER	Maximum number of messages of subshard
ENQUEUED_MSGS	NUMBER	Number of messages enqueued for the subshard
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 subshard
NUM_FREE_CHUNKS	NUMBER	Number of free chunks for the subshard
USED_MEMORY_SIZE	NUMBER	Total estimated size of memory in use (in bytes) for the subshard
STATE	VARCHAR2(13)	Subshard 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

See Also:

Oracle Database Advanced Queuing User's Guide for more information about Oracle Database Advanced Queueing