FIX: SQL Server Analysis Services 2005 system performance may be slow after you use the ADOMD.NET data provider to run an MDX query that returns a large result set from a cube

This article describes the following about this hotfix release:

• The issues that are fixed by this hotfix package
• The prerequisites for installing the hotfix package
• Information about whether you must restart the computer after you install the hotfix package
• Information about whether the hotfix package is replaced by any other hotfix package
• Information about whether you must make any registry changes
• The files that are contained in the hotfix package

Consider the following scenario. You use the ADOMD.NET data provider in Microsoft SQL Server 2005 Analysis Services to run a Multidimensional Expressions (MDX) query. The MDX query retrieves a large result set from a cube. In this scenario, SQL Server 2005 system performance may be slow. When this problem occurs, the duration of the process to retrieve a result set increases exponentially as the number of rows that the query returns in the result set increases.

Note You may not notice decreased performance for queries that contain fewer than 5,000 rows.

This problem occurs because the ADOMD.NET data provider incorrectly keeps track of the current position in the result set. When the ADOMD.NET data provider incorrectly keeps track of the current position in the result set, each request to retrieve a row requires Analysis Services to iterate from the start of the result set to the requested row.

For example, a request to retrieve rows 499 and 500 requires Analysis Services to iterate row 001 to row 499, iterate row 001 to row 499 again, and then iterate row 500.

Service pack information

To resolve this problem, obtain the latest service pack for SQL Server 2005. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

Hotfix information

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: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.

Prerequisites

You must have Microsoft SQL Server 2005 Service Pack 1 (SP1) installed to apply this hotfix.

For more information about how to obtain SQL Server 2005 Service Pack 1, click the following article number to view the article in the Microsoft Knowledge Base:

Restart information

After you apply this hotfix, you do not have to restart the computer if the following conditions are true:

• If Analysis Services is running as a named instance, you stop the SQL Server Browser service before you apply this hotfix.
• You exit all Analysis Services tools and all client applications before you apply this hotfix.
• You exit Microsoft Internet Information Services (IIS) before you apply this hotfix.

Registry information

You do not have to change the registry.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

Hotfix file information

This hotfix contains only those files that are required to correct the issues that this article lists. This hotfix may not contain of 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.

SQL Server 2005 Analysis Services hotfix, 32-bit

SQL Server 2005 Analysis Services hotfix, 64-bit

SQL Server 2005 Analysis Services hotfix, 64-bit for Itanium processors

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section. This problem was first corrected in SQL Server 2005 Service Pack 2.

For more information, click the following article number to view the article in the Microsoft Knowledge Base: