Уровень изоляции транзакций MS SQL

SELECT CASE transaction_isolation_level
WHEN 0 THEN 'Unspecified'
WHEN 1 THEN 'ReadUncomitted'
WHEN 2 THEN 'ReadComitted'
WHEN 3 THEN 'Repeatable'
WHEN 4 THEN 'Serializable'
WHEN 5 THEN 'Snapshot'
END AS TIL
FROM sys.dm_exec_sessions
WHERE session_id = @@SPID