Microsoft distributes Microsoft SQL Server 2005 or Microsoft SQL Server 2008 or 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 2005 or Microsoft SQL Server 2008 or Microsoft SQL Server 2008 R2 fix release.
Symptoms
Consider the following scenario. You have a database in Microsoft SQL Server 2005 or Microsoft SQL Server 2008 or Microsoft SQL Server 2008 R2. You run a query that contains multiple self-join operations on the same column of a table in the database. For example, when you try to create a cube that uses the data in the database, a query which contains multiple self-join operations on the same column might be executed. In this scenario, poor performance may occur, and the query may take a long time to be executed.
Cause
This issue occurs because the cardinality estimation in the query is incorrect. After several self-join operations are considered, the query optimizer may estimate the number of rows for another join operator to be 1. Therefore, the query optimizer selects an inefficient query plan and poor performance may occur.
Resolution
Cumulative update information
SQL Server 2008 Service Pack 2
The fix for this issue was first released in Cumulative Update 3 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:
2498535 Cumulative update package 3 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.
SQL Server 2008 R2
The fix for this issue was first released in Cumulative Update 6. 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:
2489376 Cumulative Update package 6 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
SQL Server 2008 Service Pack 1
The fix for this issue was first released in Cumulative Update 12 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:
2467236 Cumulative update package 12 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. 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 install this cumulative update package, you must enable traceflag 4199. To do this, you can add the -T4199 startup parameter, or you can use the dbcc traceon(4199) statement for an individual session.
SQL Server 2005 Service Pack 3
SQL Server 2005 Service Pack 3 The fix for this issue was first released in Cumulative Update 13 for SQL Server 2005 Service Pack 3. For more information about this cumulative update package, click the following article number to view the article in the Microsoft Knowledge Base:
2438344 Cumulative update package 13 for SQL Server 2005 Service Pack 3Note 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 2005 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:
960598 The SQL Server 2005 builds that were released after SQL Server 2005 Service Pack 3 was released Microsoft SQL Server 2005 hotfixes are created for specific SQL Server service packs. You must apply a SQL Server 2005 Service Pack 3 hotfix to an installation of SQL Server 2005 Service Pack 3. By default, any hotfix that is provided in a SQL Server service pack is included in the next SQL Server service pack.
After you install this cumulative update package, you must enable traceflag 4199. To do this, you can add the -T4199 startup parameter, or you can use the dbcc traceon(4199) statement for an individual session.
SQL Server 2005 Service Pack 4
The fix for this issue was first released in Cumulative Update 2 for SQL Server 2005 Service Pack 4. For more information about this cumulative update package, click the following article number to view the article in the Microsoft Knowledge Base:
2489409 Cumulative update package 2 for SQL Server 2005 Service Pack 4Note 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 2005 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:
2485757 The SQL Server 2005 builds that were released after SQL Server 2005 Service Pack 4 was released Microsoft SQL Server 2005 hotfixes are created for specific SQL Server service packs. You must apply a SQL Server 2005 Service Pack 4 hotfix to an installation of SQL Server 2005 Service Pack 4. By default, any hotfix that is provided in a SQL Server service pack is included in the next SQL Server service pack.
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 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:
822499New 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
