sys.dm_tran_active_transactions and sys.dm_tran_current_transaction look alike, but one lists active transactions for the instance, the other only your session.
How Many CPUs SQL Server Really Uses
CPUs SQL Server really uses depend on edition, guest topology, affinity, and online schedulers; learn to see the instance’s usable capacity.
user_lookups: Verify the Plan Before Adding Coverage
user_lookups helps identify where to investigate missing coverage. Compare complete query results and actual plans before adding included columns. Weigh the read benefit against storage and write costs.
Index Usage Snapshots: Reject Invalid Counter Deltas
Index usage snapshots require a valid counter window. Keep missing rows and lifecycle gaps visible. The guarded example rejects invalid pairs before calculating any activity delta.
Granting VIEW SERVER STATE Without Handing Out sysadmin
Grant VIEW SERVER STATE or SQL Server 2022 performance permissions to a monitoring login, add job history access, and test its limits.
Five DMVs Worth Memorizing
Five DMVs worth memorizing show SQL Server sessions, active requests, waits, index use, and file I/O during an incident.
Comparing Two Wait Stats Snapshots to See What Changed
Compare wait stats snapshots over a chosen window, subtract cumulative counters, remove background waits, and calculate rates and average waits.