Long running MS SQL QUERIES

B. Obtain information about the top five queries by average CPU time

The following example returns the text of the SQL statement and average CPU time for the top five queries.

SQLCopy

SELECT TOP 5 total_worker_time/execution_count AS [Avg CPU Time],  
    SUBSTRING(st.text, (qs.statement_start_offset/2)+1,   
        ((CASE qs.statement_end_offset  
          WHEN -1 THEN DATALENGTH(st.text)  
         ELSE qs.statement_end_offset  
         END - qs.statement_start_offset)/2) + 1) AS statement_text  
FROM sys.dm_exec_query_stats AS qs  
CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) AS st  
ORDER BY total_worker_time/execution_count DESC;  

C. Provide batch-execution statistics

The following example returns the text of SQL queries that are being executed in batches and provides statistical information about them.

SQLCopy

SELECT s2.dbid,   
    s1.sql_handle,    
    (SELECT TOP 1 SUBSTRING(s2.text,statement_start_offset / 2+1 ,   
      ( (CASE WHEN statement_end_offset = -1   
         THEN (LEN(CONVERT(nvarchar(max),s2.text)) * 2)   
         ELSE statement_end_offset END)  - statement_start_offset) / 2+1))  AS sql_statement,  
    execution_count,   
    plan_generation_num,   
    last_execution_time,     
    total_worker_time,   
    last_worker_time,   
    min_worker_time,   
    max_worker_time,  
    total_physical_reads,   
    last_physical_reads,   
    min_physical_reads,    
    max_physical_reads,    
    total_logical_writes,   
    last_logical_writes,   
    min_logical_writes,   
    max_logical_writes    
FROM sys.dm_exec_query_stats AS s1   
CROSS APPLY sys.dm_exec_sql_text(sql_handle) AS s2    
WHERE s2.objectid is null   
ORDER BY s1.sql_handle, s1.statement_start_offset, s1.statement_end_offset;  

A. Find the query text for a running batch

The following example queries sys.dm_exec_requests to find the interesting query and copy its sql_handle from the output.

SQLCopy

SELECT * FROM sys.dm_exec_requests;
GO

Then, to obtain the statement text, use the copied sql_handle with system function sys.dm_exec_sql_text(sql_handle).

SQLCopy

SELECT * FROM sys.dm_exec_sql_text(< copied sql_handle >);
GO

B. Find all locks that a running batch is holding

The following example queries sys.dm_exec_requests to find the interesting batch and copy its transaction_id from the output.

SQLCopy

SELECT * FROM sys.dm_exec_requests;
GO

Then, to find lock information, use the copied transaction_id with the system function sys.dm_tran_locks.

SQLCopy

SELECT * FROM sys.dm_tran_locks
WHERE request_owner_type = N'TRANSACTION'
    AND request_owner_id = < copied transaction_id >;
GO

C. Find all currently blocked requests

The following example queries sys.dm_exec_requests to find information about blocked requests.

SQLCopy

SELECT session_id,
    status,
    blocking_session_id,
    wait_type,
    wait_time,
    wait_resource,
    transaction_id
FROM sys.dm_exec_requests
WHERE status = N'suspended';
GO

D. Order existing requests by CPU

SQLCopy

SELECT
    [req].[session_id],
    [req].[start_time],
    [req].[cpu_time] AS [cpu_time_ms],
    OBJECT_NAME([ST].[objectid], [ST].[dbid]) AS [ObjectName],
    SUBSTRING(
        REPLACE(
            REPLACE(
                SUBSTRING(
                    [ST].[text], ([req].[statement_start_offset] / 2) + 1,
                    ((CASE [req].[statement_end_offset]
                            WHEN -1 THEN DATALENGTH([ST].[text])
                            ELSE [req].[statement_end_offset]
                        END - [req].[statement_start_offset]
                        ) / 2
                    ) + 1
                ), CHAR(10), ' '
            ), CHAR(13), ' '
        ), 1, 512
    ) AS [statement_text]
FROM
    [sys].[dm_exec_requests] AS [req]
    CROSS APPLY [sys].dm_exec_sql_text([req].[sql_handle]) AS [ST]
ORDER BY
    [req].[cpu_time] DESC;
GO