FIX: A Large Number of NULL Values in Join Columns Result in Slow Query Performance (813759)


The information in this article applies to:

  • Microsoft SQL Server 2000 Developer Edition
  • Microsoft SQL Server 2000 Standard Edition
  • Microsoft SQL Server 2000 Enterprise Edition
  • Microsoft SQL Server 2000 Personal Edition
  • Microsoft SQL Server 2000 Enterprise Evaluation Edition
  • Microsoft SQL Server 2000 Workgroup Edition
  • Microsoft SQL Server 2000 Desktop Engine (MSDE)
  • Microsoft SQL Server 2000 Developer Edition 64 bit
  • Microsoft SQL Server 2000 Enterprise Edition 64-bit
BUG #: 363798 (SHILOH_BUGS)

SYMPTOMS

A SELECT statement may perform slowly if:
  • Two tables are involved in the query.
  • One or both join columns contain a large number of NULL values.
  • You use a merge join to join the two tables.

RESOLUTION

Service pack information

To resolve this problem, obtain the latest service pack for Microsoft SQL Server 2000. For additional information, 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

Hotfix information

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 tool in Control Panel. SQL Server 2000 Service Pack 2 This hotfix build is designed to apply on a server that is running SQL Server 2000 Service Pack 2: 

   Date         Time   Version             Size   File name
   --------------------------------------------------------------
   24-Jan-2003  10:53  2000.80.732.0      29,244  Dbmslpcn.dll
   17-Jan-2003  18:23                    786,432  Distmdl.ldf
   17-Jan-2003  18:23                  2,359,296  Distmdl.mdf
   11-Dec-2002  09:50                        180  Drop_repl_hotfix.sql
   02-Jul-2002  07:35  2000.80.650.0     107,088  Impprov.dll
   11-Dec-2002  09:50                      1,402  Inst_repl_hotfix.sql
   17-Jan-2003  12:33                    774,409  Instdist.sql
   20-Aug-2002  08:24  2000.80.679.0     111,172  Logread.exe
   15-Dec-2002  15:21  2000.80.717.0      90,692  Msgprox.dll
   06-Apr-2002  18:08  2000.80.606.0      62,024  Odsole70.dll
   02-Jan-2002  17:59                     18,185  Qfe356326.sql
   20-Aug-2002  08:47  2000.80.679.0     135,748  Qrdrsvc.exe
   26-Aug-2002  14:49  2000.80.679.0     406,088  Rdistcom.dll
   03-Oct-2001  17:36                    437,302  Replcom.sql
   20-Aug-2002  08:33  2000.80.679.0     152,136  Replmerg.exe
   25-Nov-2002  13:43                  1,004,990  Replmerg.sql
   15-Dec-2002  15:21  2000.80.717.0     221,768  Replprov.dll
   15-Dec-2002  15:21  2000.80.717.0     303,688  Replrec.dll
   22-Jan-2003  11:27                  1,002,101  Replsys.sql
   03-Oct-2001  17:36                    881,228  Repltran.sql
   26-Aug-2002  14:49  2000.80.679.0     283,208  Rinitcom.dll
   16-Sep-2002  14:31                    390,045  Securityhotfix.sql
   26-Aug-2002  14:49  2000.80.679.0      28,672  Sqlagent.dll
   26-Aug-2002  10:39  2000.80.679.0     311,872  Sqlagent.exe
   28-Aug-2002  08:32  2000.80.679.0      49,152  Sqlagent.rll
   26-Aug-2002  14:49  2000.80.679.0      53,824  Sqlcmdss.dll
   28-Aug-2002  08:40  2000.80.679.0      12,288  Sqlcmdss.rll
   14-Jan-2003  13:39  2000.80.725.0     172,600  Sqlmap70.dll
   31-Jan-2003  18:30  2000.80.733.0   7,479,377  Sqlservr.exe
   01-Nov-2002  10:56  2000.80.698.0      45,644  Sqlvdi.dll
   24-Jan-2003  10:53  2000.80.732.0      29,244  Ssmslpcn.dll
   24-Jan-2003  10:53  2000.80.732.0      82,492  Ssnetlib.dll
   02-Jan-2003  12:12  2000.80.722.0      25,148  Ssnmpn70.dll
   06-Apr-2002  18:08  2000.80.606.0      70,208  Xplog70.dll
   06-Apr-2002  18:08  2000.80.606.0      53,828  Xpqueue.dll
   06-Apr-2002  18:08  2000.80.606.0     156,228  Xprepl.dll
   11-Jul-2002  17:00  2000.80.658.0     279,104  Xpstar.dll
   16-Sep-2002  15:12  2000.80.686.0      98,872  Xpweb70.dll

SQL Server 2000 Service Pack 3 This hotfix build is designed to apply on a server that is running SQL Server 2000 Service Pack 3:

   Date         Time   Version             Size   File name
   --------------------------------------------------------------
   08-Feb-2003  05:43                    786,432  Distmdl.ldf
   08-Feb-2003  05:43                  2,359,296  Distmdl.mdf
   30-Jan-2003  01:55                        180  Drop_repl_hotfix.sql
   30-Jan-2003  05:18                    746,470  Instdist.sql
   30-Jan-2003  01:55                      1,402  Inst_repl_hotfix.sql
   08-Feb-2003  06:40  2000.80.765.0      90,692  Msgprox.dll      
   08-Feb-2003  03:53                  1,065,895  Replmerg.sql
   08-Feb-2003  06:40  2000.80.765.0     221,768  Replprov.dll     
   08-Feb-2003  06:40  2000.80.765.0     307,784  Replrec.dll      
   30-Jan-2003  05:18                  1,084,318  Replsys.sql
   08-Feb-2003  06:40  2000.80.765.0     176,696  Sqlmap70.dll     
   08-Feb-2003  06:40  2000.80.765.0      57,920  Sqlrepss.dll     
   08-Feb-2003  06:41  2000.80.765.0   7,528,529  Sqlservr.exe     
   08-Feb-2003  06:40  2000.80.765.0      45,644  Sqlvdi.dll       
   08-Feb-2003  06:40  2000.80.765.0      82,492  Ssnetlib.dll

Note Because of file dependencies, the most recent hotfix or feature that contains these files may also contain additional files.


STATUS

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 Microsoft SQL Server 2000 Service Pack 4.
Modification Type:MinorLast Reviewed:9/27/2005
Keywords:kbHotfixServer kbQFE kbQFE kbSQLServ2000preSP4fix kbfix kbbug KB813759 kbAudDeveloper
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