v$buffered_subscribers

'LAST_DEQUEUED_SEQ  : ' ||  LAST_DEQUEUED_SEQ|| chr(10) ||
'LAST_DEQUEUED_NUM  : ' ||  LAST_DEQUEUED_NUM || chr(10) ||
'CURRENT_ENQ_SEQ    : ' ||  CURRENT_ENQ_SEQ   || chr(10) ||
'NUM_MSGS           : ' ||  NUM_MSGS          || chr(10) ||
'CNUM_MSGS          : ' ||  CNUM_MSGS         || chr(10) ||
'TOTAL_DEQUEUED_MSG : ' ||  TOTAL_DEQUEUED_MSG|| chr(10) ||
'TOTAL_SPILLED_MSG  : ' ||  TOTAL_SPILLED_MSG subscribers_details
from V$BUFFERED_SUBSCRIBERS
SEE CODE DEPOT FOR FULL SCRIPT
/

When the above statement is executed at Apply side, subscriber_name shows the name of the Apply process.

A typical output is displayed below:

SUBSCRIBERS_DETAILS
-----------------------------
QUEUE_NAME         : LN4_QUEUE
SUBSCRIBER_NAME    : LN4_APPLY
SUBSCRIBER_ADDRESS :
SUBSCRIBER_TYPE    : SUBSCRIBER
STARTUP_TIME       : 20-OCT-04
LAST_BROWSED_SEQ   : 9308
LAST_BROWSED_NUM   : 9308
LAST_DEQUEUED_SEQ  : 9308
LAST_DEQUEUED_NUM  : 9308
CURRENT_ENQ_SEQ    : 0
NUM_MSGS           : 0
CNUM_MSGS          : 9308
TOTAL_DEQUEUED_MSG : 9308
TOTAL_SPILLED_MSG  : 31