[sql-server] Finding blocking/locking queries in MS SQL (mssql)

Using sys.dm_os_wait_stats I have identified what I believe is a locking problem

  wait type    waittime  pct     running ptc
  LCK_M_RS_S   2238.54   22.14   22.14
  LCK_M_S      1980.59   19.59   41.73

Is there a way I can find the top blocking/locking queries? I've tried querying sys.dm_db_index_operational_stats without much luck.

The answer is


You may find this query useful:

SELECT * 
FROM sys.dm_exec_requests
WHERE DB_NAME(database_id) = 'YourDBName' 
AND blocking_session_id <> 0

I found this query which helped me find my locked table and query causing the issue.

SELECT  L.request_session_id AS SPID, 
        DB_NAME(L.resource_database_id) AS DatabaseName,
        O.Name AS LockedObjectName, 
        P.object_id AS LockedObjectId, 
        L.resource_type AS LockedResource, 
        L.request_mode AS LockType,
        ST.text AS SqlStatementText,        
        ES.login_name AS LoginName,
        ES.host_name AS HostName,
        TST.is_user_transaction as IsUserTransaction,
        AT.name as TransactionName,
        CN.auth_scheme as AuthenticationMethod
FROM    sys.dm_tran_locks L
        JOIN sys.partitions P ON P.hobt_id = L.resource_associated_entity_id
        JOIN sys.objects O ON O.object_id = P.object_id
        JOIN sys.dm_exec_sessions ES ON ES.session_id = L.request_session_id
        JOIN sys.dm_tran_session_transactions TST ON ES.session_id = TST.session_id
        JOIN sys.dm_tran_active_transactions AT ON TST.transaction_id = AT.transaction_id
        JOIN sys.dm_exec_connections CN ON CN.session_id = ES.session_id
        CROSS APPLY sys.dm_exec_sql_text(CN.most_recent_sql_handle) AS ST
WHERE   resource_database_id = db_id()
ORDER BY L.request_session_id

Use the script: sp_blocker_pss08 or SQL Trace/Profiler and the Blocked Process Report event class.


Examples related to sql-server

Passing multiple values for same variable in stored procedure SQL permissions for roles Count the Number of Tables in a SQL Server Database Visual Studio 2017 does not have Business Intelligence Integration Services/Projects ALTER TABLE DROP COLUMN failed because one or more objects access this column Create Local SQL Server database How to create temp table using Create statement in SQL Server? SQL Query Where Date = Today Minus 7 Days How do I pass a list as a parameter in a stored procedure? SQL Server date format yyyymmdd

Examples related to sql-server-2005

Add a row number to result set of a SQL query SQL Server : Transpose rows to columns Select info from table where row has max date How to query for Xml values and attributes from table in SQL Server? How to restore SQL Server 2014 backup in SQL Server 2008 SQL Server 2005 Using CHARINDEX() To split a string Is it necessary to use # for creating temp tables in SQL server? SQL Query to find the last day of the month JDBC connection to MSSQL server in windows authentication mode How to convert the system date format to dd/mm/yy in SQL Server 2008 R2?

Examples related to sql-server-2008

Violation of PRIMARY KEY constraint. Cannot insert duplicate key in object How to Use Multiple Columns in Partition By And Ensure No Duplicate Row is Returned SQL Server : How to test if a string has only digit characters Conversion of a varchar data type to a datetime data type resulted in an out-of-range value in SQL query Get last 30 day records from today date in SQL Server How to subtract 30 days from the current date using SQL Server Calculate time difference in minutes in SQL Server SQL Connection Error: System.Data.SqlClient.SqlException (0x80131904) SQL Server Service not available in service list after installation of SQL Server Management Studio How to delete large data of table in SQL without log?

Examples related to query-optimization

How to do the Recursive SELECT query in MySQL? What is the optimal way to compare dates in Microsoft SQL server? How to find out what is locking my tables? Finding blocking/locking queries in MS SQL (mssql) SQL: How to properly check if a record exists Counting DISTINCT over multiple columns JOIN queries vs multiple queries PostgreSQL - fetch the row which has the Max value for a column mysql select from n last rows