Microsoft KB Archive/919165

= FIX: A memory leak occurs when you run a remote query by using a linked server in SQL Server 2000 =

Article ID: 919165

Article Last Modified on 11/2/2007

-

APPLIES TO


 * Microsoft SQL Server 2000 Personal Edition
 * Microsoft SQL Server 2000 Developer Edition
 * Microsoft SQL Server 2000 Enterprise Edition
 * Microsoft SQL Server 2000 Standard Edition

-



Bug #: 50000168 (SQL Hotfix)

Bug #: 482034 (SQL Server 8.0)



Microsoft distributes Microsoft SQL Server 2000 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 2000 fix release.



SUMMARY
This article describes the following about this hotfix release:
 * The issues that are fixed by the hotfix package
 * The prerequisites for installing the hotfix package
 * Whether you must restart the computer after you install the hotfix package
 * Whether you must make any registry changes
 * The files that are contained in the hotfix package



SYMPTOMS
When you run a remote query by using a linked server in Microsoft SQL Server 2000, a memory leak occurs. This problem occurs when the following conditions are true:
 * The query returns variable-length data that is 256 bytes or larger. For example, the query returns a column, and the type of the column is the varchar(256) data type or the nvarchar(128) data type.
 * The execution plan for the query contains the Hash Match operator or the Table Spool operator.
 * After the Hash Match operator or the Table Spool operator, the execution plan for the query contains an operator that stops retrieving rows before the end of the remote rowset. For example, the execution plan for the query contains the TOP operator.

For a list of all publicly released SQL Server 2000 post-service pack hotfixes, click the following article number to view the article in the Microsoft Knowledge Base:

894905 Cumulative list of the hotfixes that are available for SQL Server 2000 Service Pack 4



CAUSE
This problem occurs because SQL Server 2000 uses multiple-row optimization during the remote query execution. This optimization was introduced to improve remote query performance in SQL Server 2000. For providers that support a DBPROP_MAXOPENROWS property value that is greater than 1, SQL Server 2000 may fetch multiple rows and may not release row handles. SQL Server 2000 may do this if an operator stops fetching before all the rows are processed.



RESOLUTION
The installer does not install this hotfix correctly on x64-based systems. This installation issue occurs when the following conditions are true:
 * The system uses the Advanced Micro Devices (AMD) AMD64 processor architecture or the Intel Extended Memory 64 Technology (EM64T) processor architecture.

Note This issue does not occur on systems that use the Intel Itanium processor architecture.
 * The system is running a 64-bit version of the Microsoft Windows Server operating system.
 * The system is running a 32-bit version of SQL Server 2000.

We have corrected this installation issue in later builds of SQL Server 2000, starting with version 8.00.2244. When a customer who is running SQL Server 2000 on an x64-based system requests this hotfix, we will provide a build that includes this hotfix and that can be installed correctly on an x64-based system. The build that we provide will be version 8.00.2244 or a later version.

Hotfix information
A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Only apply it to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next SQL Server 2000 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the hotfix. For a complete list of Microsoft Product Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:

http://support.microsoft.com/contactus/?ws=support

Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

Prerequisites
 Microsoft SQL Server 2000 Service Pack 4 (SP4)

For information about how to obtain SQL Server 2000 SP4, click the following article number to view the article in the Microsoft Knowledge Base:

290211 How to obtain the latest SQL Server 2000 service pack



Restart information
You do not have to restart the computer after you apply this hotfix. The SQL Server service stops when you apply this hotfix.

Registry information
You do not have to change the registry.

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 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 2000, 32-bit version


STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the &quot;Applies to&quot; section.



MORE INFORMATION
For more information, 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

Keywords: kbbug kbfix kbtshoot kbhotfixserver kbqfe kbpubtypekc KB919165

-

[mailto:TECHNET@MICROSOFT.COM Send feedback to Microsoft]

© Microsoft Corporation. All rights reserved.