Microsoft distributes Microsoft SQL Server 2005 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 fix release.
If you are a Small Business customer, find additional troubleshooting and learning resources at the Support for Small Business site.
You have a complex query in Microsoft SQL Server 2005. The execution plan of the query contains semi join operators. When you run the query, the query performance of the query is slow compared to Microsoft SQL Server 2000.
Note Typically, semi join operators are generated when the query contains the IN keyword or the EXISTS keyword.
This problem occurs because the query optimizer generates many more execution plans than SQL Server 2000 does. Therefore, the query optimizer may time out. When this occurs, the query optimizer stops searching for executing plans before the query optimizer fully searches all possible executing plans.
To determine whether the query optimizer times out, search for the StatementOptmEarlyAbortReason="TimeOut" expression in the XML output of the Showplan execution plan.
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.
If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.
Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site:
How to obtain the latest service pack for SQL Server 2005
You do not have to restart the computer after you apply this hotfix.
Hotfix replacement information
This hotfix is not replaced by any other hotfix.
You do not have to change the registry.
This hotfix contains only those files that are required to correct the issues that this article lists. This hotfix may not contain all the files that you must have to fully update a product to the latest build.
The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.
After you apply this hotfix, you must enable trace flag 4102 and trace flag 4118 so that the behavior reverts to the behavior in SQL Server 2000. However, we recommend that you use the method that is described in the "Workaround" section before you apply this hotfix.
You must use these trace flags for a connection on the server or for all connections on the server. If you set the trace flags at startup, the trace flags affect all connections on the server.
For more information about how to set trace flags, see the following topics in SQL Server 2005 Books Online:
DBCC TRACEON (Transact-SQL)
Trace flags (Transact-SQL)
DBCC TRACESTATUS (Transact-SQL)
Breaking changes to Database Engine features in SQL Server 2005
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: