SQL Server で現在のトランザクション開始時刻を取得する

https://docs.microsoft.com/ja-jp/sql/relational-databases/system-dynamic-management-views/sys-dm-tran-active-transactions-transact-sql?view=sql-server-ver15
https://docs.microsoft.com/ja-jp/sql/relational-databases/system-dynamic-management-views/sys-dm-tran-current-transaction-transact-sql?view=sql-server-ver15

select transaction_begin_time from sys.dm_tran_active_transactions
 where transaction_id = (select transaction_id from sys.dm_tran_current_transaction)