Du kannst die Session-ID der Abfrage auslesen
SELECT
r.session_id,
r.status,
r.start_time,
r.command,
r.cpu_time,
r.total_elapsed_time,
r.reads,
r.writes,
r.logical_reads,
r.wait_type,
r.wait_time,
r.last_wait_type,
r.blocking_session_id,
t.text AS query_text,
s.host_name,
s.program_name,
s.login_name
FROM
sys.dm_exec_requests AS r
JOIN
sys.dm_exec_sessions AS s ON r.session_id = s.session_id
CROSS APPLY
sys.dm_exec_sql_text(r.sql_handle) AS t
WHERE
r.session_id <> @@SPID; -- Eigene Abfrage ausnehmen
Und die Session danach mit
KILL <Session-ID>
beenden.