V$LOCK
This view lists the locks held by the database.
Fields
The most relevant view fields are:
SID
: An identifier for the session holding or acquiring the lockID1
: Lock identifier #1 (depends onTYPE
)ID2
: Lock identifier #2 (depends onTYPE
)TYPE
: The type of lock; user locks can beTM
(DML enqueue),TX
(transaction enqueue), orUL
(user supplied)LMODE
: A lock mode in which the session holds the lock; values can be:NONE
NULL (NULL)
ROW-S (SS)
ROW-X
SHARE (S)
S/ROW-X (SSX)
EXCLUSIVE (X)
REQUEST
: A lock mode in which the process request locks; values are the same as for theLMODE
fieldCTIME
: The time since current mode was grantedBLOCK
: If the lock is blocking another lock the value is 1, otherwise the value is 0
See also
- The
DBA_BLOCKERS
,DBA_WAITERS
, ...
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