Dynamic Performance (V$) Views, 211 of 238

V$STREAMS_APPLY_READER

V$STREAMS_APPLY_READER displays information about each apply reader. The apply reader for an apply process is a process which reads (dequeues) messages from the queue, computes message dependencies, builds transactions, and passes the transactions on to the apply process coordinator in commit order for assignment to the apply servers.

Column	Datatype	Description
`SID`	`NUMBER`	Session ID of the reader's session
`SERIAL#`	`NUMBER`	Serial number of the reader's session
`APPLY#`	`NUMBER`	Apply process number. An apply process is an Oracle background process, prefixed by `ap`.
`APPLY_NAME`	`VARCHAR2(30)`	Name of the apply process
`STATE`	`VARCHAR2(17)`	State of the reader: `IDLE` `DEQUEUE MESSAGES` `SCHEDULE MESSAGES`
`TOTAL_MESSAGES_DEQUEUED`	`NUMBER`	Total number of messages dequeued since the apply process was last started
`DEQUEUE_TIME`	`DATE`	Time last message was received
`DEQUEUED_MESSAGE_NUMBER`	`NUMBER`	Number of the last message received
`DEQUEUED_MESSAGE_CREATE_TIME`	`DATE`	For captured messages, creation time at the source database of the last message received. For user-enqueued messages, time when the message was enqueued into the queue at the local database.
`SGA_USED`	`NUMBER`	Amount of SGA memory used (in bytes) by the apply process since it was last started
`ELAPSED_DEQUEUE_TIME`	`NUMBER`	Time elapsed (in hundreths of a second) dequeuing messages since the apply process was last started
`ELAPSED_SCHEDULE_TIME`	`NUMBER`	Time elapsed (in hundreths of a second) scheduling messages since the apply process was last started. Scheduling includes computing dependencies between messages and assembling messages into transactions.

Note:

The ELAPSED_DEQUEUE_TIME and ELAPSED_SCHEDULE_TIME columns are only populated if the TIMED_STATISTICS initialization parameter is set to true, or if the STATISTICS_LEVEL initialization parameter is set to TYPICAL or ALL.