Microsoft distributes Microsoft SQL Server 2008 or SQL 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 2008 R2 fix release.
Symptoms
You run a common table expression (CTE)-based query that uses the CHANGETABLE function against a Microsoft SQL Server 2008 or SQL Server 2008 R2 table that has change tracking enabled. Unexpectedly, the query runs very slowly even though only a few rows are returned.
Cause
The issue occurs because SQL Server selects an inefficient query plan. This causes many read executes to return the result.
Resolution
To enable the fix for this issue, you must enable the -T8295Â SQL Server trace flag.
Be aware that you should investigate your performance problem before you enable this trace flag. We do not recommend that you enable this trace flag unless instructed by Microsoft Support Services, or unless you have validated on a pre-production platform that the performance of your Change Tracking queries improve and that the other performance aspects of your system are not affected.
Cumulative update information
SQL Server 2008 R2 Service Pack 1
The fix for this issue was first released in Cumulative Update 1 for SQL Server 2008 R2 Service Pack 1. For more information about how to obtain this cumulative update package, click the following article number to view the article in the Microsoft Knowledge Base:
2544793 Cumulative Update package 1 for SQL Server 2008 R2 Service Pack 1Note 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:
2567616 The SQL Server 2008 R2 builds that were released after SQL Server 2008 R2 Service Pack 1 was released
SQL Server 2008 Service Pack 2
The fix for this issue was first released in Cumulative Update 4 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:
2527180 Cumulative update package 4 for SQL Server 2008 Service Pack 2Note 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:
2402659 The SQL Server 2008 builds that were released after SQL Server 2008 Service Pack 2 was released Microsoft SQL Server 2008 hotfixes are created for specific SQL Server service packs. You must apply a SQL Server 2008 Service Pack 2 hotfix to an installation of SQL Server 2008 Service Pack 2. By default, any hotfix that is provided in a SQL Server service pack is included in the next SQL Server service pack.
The fix for this issue was first released in Cumulative update package 13. For more information about how to obtain this cumulative update package for SQL Server 2008 Service Pack 1, click the following article number to view the article in the Microsoft Knowledge Base:
2497673 Cumulative update package 13 for SQL Server 2008 Service Pack 1Note 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:
956909 The SQL Server 2008 builds that were released after SQL Server 2008 was released
SQL Server 2008 R2
The fix for this issue was first released in Cumulative Update 7. 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:
2507770 Cumulative Update package 7 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.
More Information
For more information about what files are changed, and for information about any prerequisites to apply the cumulative update package that contains the hotfix that is described in this Microsoft Knowledge Base article, click the following article number to view the article in the Microsoft Knowledge Base:
2497673 Cumulative update package 13 for SQL Server 2008 Service Pack 1
References
For more information about the list of builds that are available after the release of SQL Server 2008, click the following article number to view the article in the Microsoft Knowledge Base:
956909 The SQL Server 2008 builds that were released after SQL Server 2008 was releasedFor 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 problemsFor 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 packagesFor 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
