FIX: Clustered index is not used in the execution plan in SQL Server 2008 R2 if a query uses two or more partitions

Consider the following scenario:

• You create two or more partitions on a column of a table in Microsoft SQL Server 2008 R2.
• You create a clustered index on a different column of the same table.
• You run a query against the table. The query uses two or more of the partitions.

In this scenario, slow performance occurs, and a sort operation is used in the execution plan instead of the clustered index.

Cumulative update information

SQL Server 2008 R2

The fix for this issue was first released in cumulative update package 10. 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:Note Because the builds are cumulative, each new update release contains all the hotfixes and all the security updates that were included with the previous SQL Server 2008 R2 update release. We recommend that you consider applying the most recent update release that contains this hotfix. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

SQL Server 2008 R2 Service Pack 1

The fix for this issue was first released in Cumulative Update 4 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: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:

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