FIX: Query performance decreases after you upgrade to SQL Server 2008 or SQL Server 2008 R2 from SQL Server 2000 if the query uses a user-defined scalar function

Article translations Article translations
Article ID: 2260502 - View products that this article applies to.
Microsoft distributes Microsoft SQL Server 2008 and Microsoft SQL Server 2008 R2 fixes as one downloadable file. Because the fixes are cumulative, each new release contains all the hotfixes and all the security fixes that were included with the previous SQL Server 2008 or SQL Server 2008 R2 fix release.
Expand all | Collapse all

On This Page

SYMPTOMS

Consider the following scenario:
  • You upgrade Microsoft SQL Server 2000 to Microsoft SQL Server 2008 or SQL Server 2008 R2.
  • You run a query that uses a user-defined scalar function.

In this scenario, the query may require more time to complete compared to the time that is required before the upgrade.

Note This issue usually occurs when a nondeterministic function accesses data in the database.

CAUSE

This issue occurs because a suboptimal query plan is created for the query. Therefore, the user-defined scalar function is called more times than necessary.

RESOLUTION

Cumulative update information

SQL Server 2008 Service Pack 1

The fix for this issue was first released in Cumulative Update 10 for SQL Server 2008 Service Pack 1. For more information about this cumulative update package, click the following article number to view the article in the Microsoft Knowledge Base:
2279604 Cumulative update package 10 for SQL Server 2008 Service Pack 1
Note Because the builds are cumulative, each new fix release contains all the hotfixes and all the security fixes that were included with the previous SQL Server 2008 fix release. Microsoft recommends that you consider applying the most recent fix release that contains this hotfix. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
970365 The SQL Server 2008 builds that were released after SQL Server 2008 Service Pack 1 was released
Microsoft SQL Server 2008 hotfixes are created for specific SQL Server service packs. You must apply a SQL Server 2008 Service Pack 1 hotfix to an installation of SQL Server 2008 Service Pack 1. By default, any hotfix that is provided in a SQL Server service pack is included in the next SQL Server service pack.

After you apply the cumulative update, you must enable trace flag 4199 to enable the fix. You can enable the trace flag by running the "DBCC TRACEON(4199, -1)" command for an individual session, or by adding the "-T4199" startup parameter.

SQL Server 2008 Service Pack 2

The fix for this issue was first released in Cumulative Update 1 for SQL Server 2008 Service Pack 2. For more information about this cumulative update package, click the following article number to view the article in the Microsoft Knowledge Base:
2289254 Cumulative update 1 for SQL Server 2008 Service Pack 2
Note Because the builds are cumulative, each new fix release contains all the hotfixes and all the security fixes that were included with the previous SQL Server 2008 fix release. We recommend that you consider applying the most recent fix release that contains this hotfix. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
2402659 The SQL Server 2008 builds that were released after SQL Server 2008 Service Pack 2 was released

SQL Server 2008 R2

The fix for this issue was first released in Cumulative Update 5. For more information about how to obtain this cumulative update package for SQL Server 2008 R2, click the following article number to view the article in the Microsoft Knowledge Base:
2438347 Cumulative Update package 5 for SQL Server 2008 R2
Note Because the builds are cumulative, each new fix release contains all the hotfixes and all the security fixes that were included with the previous SQL Server 2008 R2 fix release. We recommend that you consider applying the most recent fix release that contains this hotfix. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
981356 The SQL Server 2008 R2 builds that were released after SQL Server 2008 R2 was released

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

REFERENCES

For more information about how to design user-defined functions, visit the following Microsoft Developer Network (MSDN) website:
General information about how to design user-defined functions
For more information about the Incremental Servicing Model for SQL Server, click the following article number to view the article in the Microsoft Knowledge Base:
935897 An Incremental Servicing Model is available from the SQL Server team to deliver hotfixes for reported problems
For more information about the naming schema for SQL Server updates, click the following article number to view the article in the Microsoft Knowledge Base:
822499 New naming schema for Microsoft SQL Server software update packages
For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:
824684 Description of the standard terminology that is used to describe Microsoft software updates

Properties

Article ID: 2260502 - Last Review: December 20, 2010 - Revision: 4.0
APPLIES TO
  • Microsoft SQL Server 2008 Developer
  • Microsoft SQL Server 2008 Enterprise
  • Microsoft SQL Server 2008 Enterprise Evaluation
  • Microsoft SQL Server 2008 Service Pack 1
  • Microsoft SQL Server 2008 Standard
  • Microsoft SQL Server 2008 Workgroup
Keywords: 
kbqfe kbfix kbsurveynew kbexpertiseadvanced KB2260502

Give Feedback

 

Contact us for more help

Contact us for more help
Connect with Answer Desk for expert help.
Get more support from smallbusiness.support.microsoft.com