Query text during caching in SQL 2005

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Query text during caching in SQL 2005

Hardy21

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November 14, 2010 at 8:09 am

#242891

Comments posted to this topic are about the item Query text during caching in SQL 2005
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Ron McCullough SSC Guru Points: 63877 More actions · Answer 1

Nice question ... learned something

If everything seems to be going well, you have obviously overlooked something.

Ron

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Carlo Romagnano SSC-Insane Points: 22596 More actions · Answer 2

Very bad worded question:

Query text during caching in SQL 2005

This is related to SQL Server caching. What should be the output of following T-SQL query:

USE AdventureWorks2008R2

GO

EXEC uspPrintError

GO

SELECT st.text QueryText

FROM sys.dm_exec_cached_plans

CROSS APPLY sys.dm_exec_sql_text(plan_handle) AS st

WHERE text LIKE N'%uspPrintError%';

In the title, it refers to sql2005, than it uses AdventureWorks2008R2

In sql2005, I get an error:

"plan_handle" is not a recognized table hints option.

I also tried to run

SELECT text FROM sys.dm_exec_sql_text(0x0500FF7F79BB1808C8808A04000000000000000000000000)

But it returns this:

-- uspPrintError prints error information about the error that caused

-- execution to jump to the CATCH block of a TRY...CATCH construct.

-- Should be executed from within the scope of a CATCH block otherwise

-- it will return without printing any error information.

CREATE PROCEDURE [dbo].[uspPrintError]

AS

BEGIN

SET NOCOUNT ON;

-- Print error information.

PRINT 'Error ' + CONVERT(varchar(50), ERROR_NUMBER()) +

', Severity ' + CONVERT(varchar(5), ERROR_SEVERITY()) +

', State ' + CONVERT(varchar(5), ERROR_STATE()) +

', Procedure ' + ISNULL(ERROR_PROCEDURE(), '-') +

', Line ' + CONVERT(varchar(5), ERROR_LINE());

PRINT ERROR_MESSAGE();

END;

At end I answered BOTH: EXEC ... and text for the stored proc.

The explanation seems to be approximate!

Hugo Kornelis SSC Guru Points: 64780 More actions · Answer 3

Good question. I answered wrong; I thought all statements were cached.

Hardik, do you have any references where I can read more about this?

Hugo Kornelis, SQL Server/Data Platform MVP (2006-2016)
Visit my SQL Server blog: https://sqlserverfast.com/blog/
SQL Server Execution Plan Reference: https://sqlserverfast.com/epr/

Hardy21 SSCrazy Eights Points: 9708 More actions · Answer 4

Carlo Romagnano (11/14/2010)
Very bad worded question:
Query text during caching in SQL 2005
This is related to SQL Server caching. What should be the output of following T-SQL query:
USE AdventureWorks2008R2
GO
EXEC uspPrintError
GO
SELECT st.text QueryText
FROM sys.dm_exec_cached_plans
CROSS APPLY sys.dm_exec_sql_text(plan_handle) AS st
WHERE text LIKE N'%uspPrintError%';
In the title, it refers to sql2005, than it uses AdventureWorks2008R2
In sql2005, I get an error:
"plan_handle" is not a recognized table hints option.
I also tried to run
SELECT text FROM sys.dm_exec_sql_text(0x0500FF7F79BB1808C8808A04000000000000000000000000)
But it returns this:
-- uspPrintError prints error information about the error that caused
-- execution to jump to the CATCH block of a TRY...CATCH construct.
-- Should be executed from within the scope of a CATCH block otherwise
-- it will return without printing any error information.
CREATE PROCEDURE [dbo].[uspPrintError]
AS
BEGIN
SET NOCOUNT ON;
-- Print error information.
PRINT 'Error ' + CONVERT(varchar(50), ERROR_NUMBER()) +
', Severity ' + CONVERT(varchar(5), ERROR_SEVERITY()) +
', State ' + CONVERT(varchar(5), ERROR_STATE()) +
', Procedure ' + ISNULL(ERROR_PROCEDURE(), '-') +
', Line ' + CONVERT(varchar(5), ERROR_LINE());
PRINT ERROR_MESSAGE();
END;
At end I answered BOTH: EXEC ... and text for the stored proc.
The explanation seems to be approximate!

Thanks Carlo for pointing out the typo mistake on header (title). This behavior is same for SQL Server 2005 & in SQL 2008 and I used AdventureWorks2008R2 database so has idea that it is SQL2k8 R2 database provided by Microsoft.

Also, thanks for the validation of explanation provided.

Thanks

Koen Verbeeck SSC Guru Points: 259085 More actions · Answer 5

Nice question, definately learned something today.

However, if I run the query in SQL Server 2008 using the AdventureWorks2008 database, I get an extra result: the select query with the cross apply used in the question itself.

Need an answer? No, you need a question
My blog at https://sqlkover.com.
MCSE Business Intelligence - Microsoft Data Platform MVP

Nakul Vachhrajani SSChampion Points: 10283 More actions · Answer 6

Good question, Hardik!

I answered wrong because I was distracted by the use of the stored procedure uspPrintError 🙂

Thanks & Regards,
Nakul Vachhrajani.
http://nakulvachhrajani.com

Follow me on
Twitter: @sqltwins

Carlo Romagnano SSC-Insane Points: 22596 More actions · Answer 7

Execute the batch without the 'GO'

EXEC uspLogError

SELECT st.text QueryText,objtype

FROM sys.dm_exec_cached_plans

CROSS APPLY sys.dm_exec_sql_text(plan_handle) AS st

WHERE text LIKE N'%uspLogError%'

Result:

CREATE PROCEDURE [dbo].[uspLogError] ....,'Proc'

EXEC uspLogError SELECT st.text QueryText FROM sys.dm_exec_cached_plans ....,'Adhoc'

The body of the stored procedure is cached in the objtype = 'Proc' (see also other info about the proc). the second record is the plan stored with objtype = 'Adhoc'

See also: http://msdn.microsoft.com/en-us/library/ms187404.aspx

cengland0 SSCertifiable Points: 6102 More actions · Answer 8

Any BOL links you can provide regarding this? There wasn't one in the explanation.

RichardDouglas SSCarpal Tunnel Points: 4029 More actions · Answer 9

Good question, thanks for taking the time to help educate the SQL community.

I look at these DMV's a lot so thankfully answered this one correctly.

Hope this helps,
Rich

[p]
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Mattrick Ten Centuries Points: 1176 More actions · Answer 10

Mattrick

Ten Centuries

Points: 1176

November 15, 2010 at 6:31 am

#1250670

Great question! Learned something new. Thanks.

jeff.mason SSCrazy Eights Points: 9585 More actions · Answer 11

It is correct to say that removing the GO between the EXEC call and the SELECT against the DMV changes the behavior. Clearly there is some caching going on at least for the duration of the batch itself, and removing it from cache when the batch completes.

Surii Default port Points: 1497 More actions · Answer 12

Learned something new from the discussion. Thanks guys.

OCTom SSChampion Points: 11785 More actions · Answer 13

The distribution of answers is almost even. That shows that this was a real brain tickler.

Oleg Netchaev SSCertifiable Points: 5276 More actions · Answer 14

Carlo Romagnano (11/14/2010)
In sql2005, I get an error:
"plan_handle" is not a recognized table hints option.

Carlo,

Please check compat level of your SQL Server 2005 AdventureWorks database. If the level is 80 then you should get "plan_handle" is not a recognized table hints option error, but if it is 90 as it should be then the script should run just fine.

Oleg