Find the Lead Blocker

---Lead Blocker


SELECT
db.name DBName,
tl.request_session_id,
wt.blocking_session_id,
OBJECT_NAME(p.OBJECT_ID) BlockedObjectName,
tl.resource_type,
h1.TEXT AS RequestingText,
h2.TEXT AS BlockingTest,
tl.request_mode
FROM sys.dm_tran_locks AS tl
INNER JOIN sys.databases db ON db.database_id = tl.resource_database_id
INNER JOIN sys.dm_os_waiting_tasks AS wt ON tl.lock_owner_address = wt.resource_address
INNER JOIN sys.partitions AS p ON p.hobt_id = tl.resource_associated_entity_id
INNER JOIN sys.dm_exec_connections ec1 ON ec1.session_id = tl.request_session_id
INNER JOIN sys.dm_exec_connections ec2 ON ec2.session_id = wt.blocking_session_id
CROSS APPLY sys.dm_exec_sql_text(ec1.most_recent_sql_handle) AS h1
CROSS APPLY sys.dm_exec_sql_text(ec2.most_recent_sql_handle) AS h2
GO

WITH LeadBlockers (blocker, blockee, level, sql)
AS
(
	SELECT	s.blocked as blocker, s.spid as blockee, 0 as level, (SELECT text FROM ::fn_get_sql(s.sql_handle)) sql
	FROM	master..sysprocesses s
	WHERE	blocked = 0 AND EXISTS (SELECT * FROM master..sysprocesses inside WHERE inside.blocked = s.spid)
	UNION ALL
	SELECT	s.blocked as blocker, s.spid as blockee, level + 1, (SELECT text FROM ::fn_get_sql(s.sql_handle)) sql
	FROM	master..sysprocesses s
			INNER JOIN LeadBlockers
					ON s.blocked = LeadBlockers.blockee
)
SELECT	*
FROM	LeadBlockers
--ORDER BY level