Cause: The session specified in an ALTER SYSTEM KILL SESSION command cannot be killed immediately because the session is involved in a non-interruptible operation (for example, rolling back a transaction or being blocked by a network operation). The session has been marked to be killed as soon as possible after the current operation is done.
Action: No action is required for the session to be killed, but further executions of the ALTER SYSTEM KILL SESSION command on this session may cause the session to be killed sooner.
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