When you run a query that performs a join between a local table and a remote table in Microsoft SQL Server 2005, the query runs very slowly. This problem occurs if the execution plan of the query contains a Left Outer Join operator that involves the local table and the remote table.

This issue does not occur in SQL Server 2000.

This issue occurs because SQL Server 2005 brings all rows instead of only the qualifying rows of the remote table to the local server when SQL Server uses an execution plan such as the execution plan that the "Symptoms" section mentions. Therefore, the query runs very slowly.

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 2005 Service Pack 2, 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 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:Microsoft SQL Server 2005 hotfixes are created for specific SQL Server service packs. You must apply a SQL Server 2005 Service Pack 2 hotfix to an installation of SQL Server 2005 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.

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

After you apply this hotfix, you must enable trace flag 4116 to enable the hotfix. To enable the trace flag, run the following statement:For example, you may experience this issue in the following scenario:

• You have a view in the local server.
• The view queries data from a remote table.
• You open a cursor for a query that runs against the view.

When you run the query, the execution plan that SQL Server generates for the FETCH operation of the cursor involves a Left Outer Join operator between the local table and the remote table. For each FETCH operation, SQL Server brings all rows in the remote table to the local server. This increases the execution time of each FETCH operation. Therefore, the time to complete the query increases.

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:

Important information for SQL Server 2005 Analysis Services

A known issue exists in Cumulative Update 7 for SQL Server 2005 Analysis Services. Consider the following scenario. You install Cumulative Update 7 for SQL Server 2005 SP2. In SQL Server Profiler, you start a trace or stop a trace. Then, you run a query. The execution time of the query exceeds the value of the ForceCommitTimeout server setting. In this scenario, all the queries that are running on the server are canceled. To work around this issue, do not run MDX queries before you start a trace or stop a trace.

For more information about the list of builds that are available after SQL Server Service Pack 2, click the following article number to view the article in the Microsoft Knowledge Base: 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:For more information about how to obtain SQL Server 2005 Service Pack 2, click the following article number to view the article in the Microsoft Knowledge Base: For more information about the new features and the improvements in SQL Server 2005 Service Pack 2, visit the following Microsoft Web site: 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:For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base: