Find out the Blocking tree in SQL Server. OR Head Blocker using script in SQL Server

Please find the below SQL Script to get Head blocker with Tree structure in SQL Server:

If exists (select * from #Temp_Table)

begin

Drop table #Temp_Table

end

else

SET NOCOUNT ON

GO

SELECT SPID, BLOCKED, REPLACE (REPLACE (T.TEXT, CHAR(10), ' '), CHAR (13), ' ' ) AS BATCH

INTO #Temp_Table

FROM sys.sysprocesses R CROSS APPLY sys.dm_exec_sql_text(R.SQL_HANDLE) T

GO

WITH BLOCKERS (SPID, BLOCKED, LEVEL, BATCH)

AS

(

SELECT SPID,

BLOCKED,

CAST (REPLICATE ('0', 4-LEN (CAST (SPID AS VARCHAR))) + CAST (SPID AS VARCHAR) AS VARCHAR (1000)) AS LEVEL,

BATCH FROM #Temp_Table R

WHERE (BLOCKED = 0 OR BLOCKED = SPID)

AND EXISTS (SELECT * FROM #Temp_Table R2 WHERE R2.BLOCKED = R.SPID AND R2.BLOCKED <> R2.SPID)

UNION ALL

SELECT R.SPID,

R.BLOCKED,

CAST (BLOCKERS.LEVEL + RIGHT (CAST ((1000 + R.SPID) AS VARCHAR (100)), 4) AS VARCHAR (1000)) AS LEVEL,

R.BATCH FROM #Temp_Table AS R

INNER JOIN BLOCKERS ON R.BLOCKED = BLOCKERS.SPID WHERE R.BLOCKED > 0 AND R.BLOCKED <> R.SPID

)

SELECT N' ' + REPLICATE (N'| ', LEN (LEVEL)/4 - 1) +

CASE WHEN (LEN(LEVEL)/4 - 1) = 0

THEN 'HEAD - '

ELSE '|----- ' END

+ CAST (SPID AS NVARCHAR (10)) + N' ' + BATCH AS BLOCKING_TREE

FROM BLOCKERS ORDER BY LEVEL ASC

GO

Output: Head blocker session id is 61.