Performance Tuning with SQL Server Dynamic Management Views

Chapter 4: Transactions
WHEN 3 THEN 'Committed'
WHEN 4 THEN 'Aborted'
WHEN 5 THEN 'Recovered'
END AS dtc_state
FROM sys.dm_tran_active_transactions DTAT
INNER JOIN sys.dm_tran_session_transactions DTST
ON DTAT.transaction_id = DTST.transaction_id
WHERE [DTST].[is_user_transaction] = 1
ORDER BY DTAT.transaction_begin_time
Listing 4.11: Querying sys.dm_db_tran_active_transactions.
Notice that we are able to isolate user transactions via a join back to sys.dm_tran_
session_transactions, filtering on the is_user_transaction column. The results
of this query are shown in Figure 4.6.
Figure 4.6: Currently active user transactions.
Had we not filtered out transactions associated with system sessions, we'd also have
seen results for hash work being performed in tempdb, similar to the record shown in
Figure 4.7.
Figure 4.7: Worktable transaction records in sys.dm_db_tran_active_transactions.
Queries against sys.dm_tran_active_transactions will often return a great number
of results that look like this, since these worktables are created and destroyed all the
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