-- transaction la plus ancienne dans la base contextuelle
DBCC OPENTRAN WITH TABLERESULTS

-- transaction de plus de n secondes (ici 30) par bases
SELECT DB_NAME(database_id), DATEDIFF(second, transaction_begin_time, GETDATE()) AS DURATION_SECOND, *
FROM   sys.dm_tran_active_transactions AS tat
       JOIN sys.dm_tran_database_transactions AS tdb 
          ON tat.transaction_id = tdb.transaction_id
WHERE  database_id > 4
  AND  DATEDIFF(second, transaction_begin_time, GETDATE()) > 30;