I heard that dba_dml_locks does not
report on sessions that are holding locked objects.
Instead, what does dba_dml_locks report on?
dba_dml_locks does not report on sessions that are
waiting on a locked object. Rather, dba_dml_locks
does report when a session is a "blocker", such as a session
is holding a lock that another session is waiting to access.
It's important to remember that the
rows returned by dba_dml_locks are sessions that
are holding blocking locks. Also see
holding DML locks
d.session_id = v.sid
d.blocking_others = 'blocking'
l.blocking_others = 'blocking';
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