Performance Tuning with SQL Server Dynamic Management Views

Chapter 2: Connections, Sessions and Requests
SELECT der.statement_start_offset ,
der.statement_end_offset ,
SUBSTRING(dest.text, der.statement_start_offset / 2,
( CASE WHEN der.statement_end_offset = -1
THEN DATALENGTH(dest.text)
ELSE der.statement_end_offset
END - der.statement_start_offset ) / 2)
AS statement_executing ,
dest.text AS [full statement code]
FROM sys.dm_exec_requests der
INNER JOIN sys.dm_exec_sessions des
ON des.session_id = der.session_id
CROSS APPLY sys.dm_exec_sql_text(der.sql_handle) dest
WHERE des.is_user_process = 1
AND der.session_id @@spid
ORDER BY der.session_id ;
Listing 2.14: Parsing the SQL text using statement_start_offset and statement_end_offset.
If you change the "" to "=" in the WHERE clause and run Listing 2.14, you'll simply get
back the text of that query, with 0 for the start offset and -1 for the end offset. If you want
to really see these offsets in action, open a tab in SSMS and run the query in Listing 2.15.
WAITFOR DELAY '00:01' ;
BEGIN TRANSACTION
-- WAITFOR DELAY '00:01' ;
INSERT INTO AdventureWorks.Production.ProductCategory
( Name, ModifiedDate )
VALUES ( 'Reflectors', GETDATE() )
ROLLBACK TRANSACTION
SELECT Name ,
ModifiedDate
FROM AdventureWorks.Production.ProductCategory
WHERE Name = 'Reflectors' ;
-- WAITFOR DELAY '00:01' ;
Listing 2.15: Investigating offsets.
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