FIX: Error 644 or 8646 May Occur During a DELETE or UPDATE Against a Table That Contains a Unicode Column with a Latin1_General

MORE INFORMATION

Assuming you are experiencing the problem described in this article, before you apply the fix provided in this article, running a DBCC CHECKDB statement will not report any errors related to the type of index corruption discussed in this article. These errors are reported after you apply the fix. The CHECKDB errors that you might see after you apply the fix may be similar to:

Server: Msg 2511, Level 16, State 1, Line 1
Table error: Object ID 2009058193, Index ID 7. Keys out of order on page (1:189), slots 184 and 185.

Note This example is specific to an error associated with a non-clustered index. However, this problem also applies to clustered indexes.

After you apply the fix and run DBCC CHECKDB, if you see error messages similar to the one indicated earlier in this article, you must rebuild the index on the table indicated in the error message to fix the corruption.

To confirm that the 644 error you are experiencing is related to the problem described in this Knowledge Base article, you can use one of the following two methods:

Method 1

For this method, follow these steps:

Apply the fix mentioned in this article on a test server.
Back up the production database (the one that is experiencing the 644 index corruption errors), and then restore the backup on the test server.
Run DBCC CHECKDB against this restored database on the test server.
Run DBCC CHECKDB against the same database on the production server.

If CHECKDB on the test server shows errors that do not show up in the CHECKDB results from the production server, then you can deduce that you are experiencing the scenario described in this article.

Method 2

For this method, follow these steps:

Identify all the tables on the affected database that have an index on a unicode column with Latin1_General_BIN collation.
If such tables exist, run the following query against those tables and see if any rows qualify this query:
```
DECLARE @i INT
SET @i = 1
WHILE @i < 32
BEGIN	
   SELECT @i, * FROM <TableName> WHERE <IndexedColumnName> LIKE N'%' + nchar(@i) + N'%' 
   SET @i = @i + 1
END
```
If the query results in any qualifying rows, then the possibility of experiencing this scenario is high (but not guaranteed yet).
To confirm that you might be experiencing the problem, run the following DELETE command against the rows that have qualified from the query:
```
BEGIN TRAN
DELETE FROM <TableName> WHERE <IndexedColumnName> = <Value>
ROLLBACK TRAN 
```
If running the query results in an error 644, then you have identified the index that has experienced the form of corruption described in this article.

After you confirm that you are experiencing the problem described in this article, follow these steps to resolve the issue:

Apply the fix discussed in this Knowledge Base article.
After you apply the fix, run DBCC CHECKDB on the affected database. Doing so should report the index corruption related errors.

These error messages will give you information about the index that is corrupted. You can use this information to rebuild the affected indexes.

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 fix has the file attributes (or later) 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.

   Date         Time   Version         Size             File name
   --------------------------------------------------------------------------
   31-May-2003  18:45  2000.80.818.0      78,400 bytes  Console.exe      
   25-Jun-2003  01:01  2000.80.818.0      33,340 bytes  Dbmslpcn.dll     
   25-Apr-2003  02:12                    786,432 bytes  Distmdl.ldf
   25-Apr-2003  02:12                  2,359,296 bytes  Distmdl.mdf
   30-Jan-2003  01:55                        180 bytes  Drop_repl_hotfix.sql
   23-Jun-2003  22:40  2000.80.837.0   1,557,052 bytes  Dtsui.dll        
   23-Jun-2003  22:40  2000.80.837.0     639,552 bytes  Dtswiz.dll       
   24-Apr-2003  02:51                    747,927 bytes  Instdist.sql
   03-May-2003  01:56                      1,581 bytes  Inst_repl_hotfix.sql
   08-Feb-2003  06:40  2000.80.765.0      90,692 bytes  Msgprox.dll      
   01-Apr-2003  02:07                      1,873 bytes  Odsole.sql
   05-Apr-2003  01:46  2000.80.800.0      62,024 bytes  Odsole70.dll     
   07-May-2003  20:41  2000.80.819.0      25,144 bytes  Opends60.dll     
   02-Apr-2003  21:48  2000.80.796.0      57,904 bytes  Osql.exe         
   02-Apr-2003  23:15  2000.80.797.0     279,104 bytes  Pfutil80.dll     
   22-May-2003  22:57                     19,195 bytes  Qfe469571.sql
   12-Jun-2003  16:37                  1,083,989 bytes  Replmerg.sql
   04-Apr-2003  21:53  2000.80.798.0     221,768 bytes  Replprov.dll     
   08-Feb-2003  06:40  2000.80.765.0     307,784 bytes  Replrec.dll      
   05-May-2003  00:05                  1,085,874 bytes  Replsys.sql
   01-Jun-2003  01:01  2000.80.818.0     492,096 bytes  Semobj.dll       
   31-May-2003  18:27  2000.80.818.0     172,032 bytes  Semobj.rll
   29-May-2003  00:29                    115,944 bytes  Sp3_serv_uni.sql
   01-Jun-2003  01:01  2000.80.818.0   4,215,360 bytes  Sqldmo.dll       
   07-Apr-2003  17:44                     25,172 bytes  Sqldumper.exe    
   19-Mar-2003  18:20  2000.80.789.0      28,672 bytes  Sqlevn70.rll
   02-Jul-2003  00:18  2000.80.834.0     180,736 bytes  Sqlmap70.dll     
   08-Feb-2003  06:40  2000.80.765.0      57,920 bytes  Sqlrepss.dll     
   23-Jun-2003  22:40  2000.80.837.0   7,553,105 bytes  Sqlservr.exe     
   08-Feb-2003  06:40  2000.80.765.0      45,644 bytes  Sqlvdi.dll       
   25-Jun-2003  01:01  2000.80.818.0      33,340 bytes  Ssmslpcn.dll     
   01-Jun-2003  01:01  2000.80.818.0      82,492 bytes  Ssnetlib.dll     
   01-Jun-2003  01:01  2000.80.818.0      25,148 bytes  Ssnmpn70.dll     
   01-Jun-2003  01:01  2000.80.818.0     158,240 bytes  Svrnetcn.dll     
   31-May-2003  18:59  2000.80.818.0      76,416 bytes  Svrnetcn.exe     
   30-Apr-2003  23:52  2000.80.816.0      45,132 bytes  Ums.dll          
   02-Jul-2003  00:19  2000.80.834.0      98,816 bytes  Xpweb70.dll

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

FIX: Error 644 or 8646 May Occur During a DELETE or UPDATE Against a Table That Contains a Unicode Column with a Latin1_General_BIN Collation (822747)