Unlike sp_who2, this custom sp_who3 only shows sessions that have a current executing request.
What is also shown is the reads and writes for the current command, along with the number of reads and writes for the entire SPID. It also shows the protocol being used (TCP, NamedPipes, or Shared Memory).
The lead blocker below will show in the BlkBy column as -1.
CREATE PROCEDURE [dbo].[sp_who3] AS BEGIN SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED SELECT SPID = er.session_id ,BlkBy = CASE WHEN lead_blocker = 1 THEN -1 ELSE er.blocking_session_id END ,ElapsedMS = er.total_elapsed_time ,CPU = er.cpu_time ,IOReads = er.logical_reads + er.reads ,IOWrites = er.writes ,Executions = ec.execution_count ,CommandType = er.command ,LastWaitType = er.last_wait_type ,ObjectName = OBJECT_SCHEMA_NAME(qt.objectid,dbid) + '.' + OBJECT_NAME(qt.objectid, qt.dbid) ,SQLStatement = SUBSTRING ( qt.text, er.statement_start_offset/2, (CASE WHEN er.statement_end_offset = -1 THEN LEN(CONVERT(nvarchar(MAX), qt.text)) * 2 ELSE er.statement_end_offset END - er.statement_start_offset)/2 ) ,STATUS = ses.STATUS ,[Login] = ses.login_name ,Host = ses.host_name ,DBName = DB_Name(er.database_id) ,StartTime = er.start_time ,Protocol = con.net_transport ,transaction_isolation = CASE ses.transaction_isolation_level WHEN 0 THEN 'Unspecified' WHEN 1 THEN 'Read Uncommitted' WHEN 2 THEN 'Read Committed' WHEN 3 THEN 'Repeatable' WHEN 4 THEN 'Serializable' WHEN 5 THEN 'Snapshot' END ,ConnectionWrites = con.num_writes ,ConnectionReads = con.num_reads ,ClientAddress = con.client_net_address ,Authentication = con.auth_scheme ,DatetimeSnapshot = GETDATE() FROM sys.dm_exec_requests er LEFT JOIN sys.dm_exec_sessions ses ON ses.session_id = er.session_id LEFT JOIN sys.dm_exec_connections con ON con.session_id = ses.session_id CROSS APPLY sys.dm_exec_sql_text(er.sql_handle) AS qt OUTER APPLY ( SELECT execution_count = MAX(cp.usecounts) FROM sys.dm_exec_cached_plans cp WHERE cp.plan_handle = er.plan_handle ) ec OUTER APPLY ( SELECT lead_blocker = 1 FROM master.dbo.sysprocesses sp WHERE sp.spid IN (SELECT blocked FROM master.dbo.sysprocesses) AND sp.blocked = 0 AND sp.spid = er.session_id ) lb ORDER BY er.blocking_session_id DESC, er.logical_reads + er.reads DESC, er.session_id END
http://sqlserverplanet.com/dba/a-better-sp_who2-using-dmvs-sp_who3
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