There are a number of blog posts that have been written on this very topic. This can be from basics to almost advanced in many ways. I am outlining some of them here below:
- SQL SERVER – Quickest Way to Identify Blocking Query and Resolution – Dirty Solution
- SQL SERVER – SSMS: Activity – All Blocking Transactions
- SQL SERVER – Find Blocking Using Blocked Process Threshold
- SQL SERVER – Activity Monitor to Identify Blocking – Find Expensive Queries
If these were not enough, I wanted to play around with some SQL Scripts for this basic deadlock behavior. The most basic script I have been using and used by many DBA will include Activity Monitor, sp_who2, sysprocesses etc.
Recently I saw a script written by a DBA friend:
SELECT * FROM sys.dm_os_waiting_tasks
WHERE blocking_session_id IS NOT NULL
GO
This shows the rows like:
This is so cool because I know who is waiting for whom. In the above image 53 is waiting for 68. While 79 is waiting for 53. This was a cool way to look at things.
I wanted to show the same data in slightly different way using T-SQL. So I wrote a Blocking Tree TSQL script.
SET NOCOUNT ON
GO
SELECT SPID, BLOCKED, REPLACE (REPLACE (T.TEXT, CHAR(10), ' '), CHAR (13), ' ' ) AS BATCH
INTO #T
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 #T R
WHERE (BLOCKED = 0 OR BLOCKED = SPID)
AND EXISTS (SELECT * FROM #T 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 #T 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
DROP TABLE #T
GO
The output would look like:
This is a cool way to look at the same Blocking data inside SSMS. I have taken a simple way to show this script. I am sure this can be beautified more with your help. So if you use this and modify the same. Do post them over comments too. That is a great way to enhance the Blocking Tree Script.
Reference: Pinal Dave (https://blog.sqlauthority.com)
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Thanks!
We can you below query as below –
——
SELECT s.session_id
,r.STATUS
,r.blocking_session_id ‘blocked by’
,r.wait_type
,wait_resource
,r.wait_time / (1000.0) ‘Wait Time (in Sec)’
,r.cpu_time
,r.logical_reads
,r.reads
,r.writes
,r.total_elapsed_time / (1000.0) ‘Elapsed Time (in Sec)’
,Substring(st.TEXT, (r.statement_start_offset / 2) + 1, (
(
CASE r.statement_end_offset
WHEN – 1
THEN Datalength(st.TEXT)
ELSE r.statement_end_offset
END – r.statement_start_offset
) / 2
) + 1) AS statement_text
,Coalesce(Quotename(Db_name(st.dbid)) + N’.’ + Quotename(Object_schema_name(st.objectid, st.dbid)) + N’.’ +
Quotename(Object_name(st.objectid, st.dbid)), ”) AS command_text
,r.command
,s.login_name
,s.host_name
,s.program_name
,s.host_process_id
,s.last_request_end_time
,s.login_time
,r.open_transaction_count
FROM sys.dm_exec_sessions AS s
INNER JOIN sys.dm_exec_requests AS r ON r.session_id = s.session_id
CROSS APPLY sys.dm_exec_sql_text(r.sql_handle) AS st
WHERE r.session_id != @@SPID
ORDER BY r.cpu_time DESC
,r.STATUS
,r.blocking_session_id
,s.session_id
Where I can use where condition like ses.login_name not in (‘xxxxx\user_login_name’).