FIX: ORDER BY DESC Query After Update Brings Error 1203

Retired KB Content Disclaimer

View products that this article applies to.

This article was previously published under Q176491

BUG #: 17495 (6.5)

SYMPTOMS

If you run an ORDER BY DESC query after an UPDATE on the same table in a transaction, you may receive the following error message:

Caller of lock manager is incorrectly trying to unlock an unlocked object. spid=%d locktype=%d dbid=%d lockid=%Id

This problem occurs if all of the following conditions are true:

The table has a clustered index.
The table has a nonclustered index on the WHERE clause condition of the UPDATE statement.
The UPDATE and SELECT statements are issued in a transaction.
There is an ORDER BY DESC clause in the SELECT statement.

This is a regression starting with SQL Server 6.5 Service Pack 2.

Back to the top

WORKAROUND

To work around this problem, do any one of the following:

Change the clustered index to a nonclustered index.
Remove the DESC keyword from the ORDER BY clause.
Remove the nonclustered index from the column that is referenced in the WHERE clause of the update.
Remove the transaction surrounding the UPDATE and SELECT statements.

Back to the top

Microsoft has confirmed this to be a problem in SQL Server 6.5. This problem has been corrected in Service Pack 5a for Microsoft SQL Server 6.5.For more information, click the following article number to view the article in the Microsoft Knowledge Base:

197177 (http://support.microsoft.com/kb/197177/ ) INF: How to Obtain SQL Server 6.5 Service Pack 5a

For more information, contact your primary support provider.

Back to the top

MORE INFORMATION

Steps to Reproduce the Problem

The following script will demonstrate the problem:

drop table test
go
create table test (c1 smallint,c2 varchar(200),c3 char(250),c4 int)
go

/* Create sample data */ 
declare @wert int
select @wert = 1

while @wert < 12
begin
 insert test values
(1,convert(varchar(200),@wert),convert(char(250),@wert),@wert)
 insert test values
(0,convert(varchar(200),@wert+1),convert(char(250),@wert+1),@wert+1)
 select @wert = @wert + 2
end
go
create unique clustered index CL_IND ON test (c1, c2)
go
create nonclustered index NCL_IND on test (c4)
go


BEGIN TRANSACTION
update test set c3 = "X" where c4 = 9
select * from test where c1 = 1 order by c1 DESC
COMMIT TRANSACTION

Back to the top

APPLIES TO

Microsoft SQL Server 6.5 Service Pack 2
Microsoft SQL Server 6.5 Service Pack 3
Microsoft SQL Server 6.5 Service Pack 4

Back to the top

kbbug kbfix kbusage KB176491

Back to the top

Retired KB Content Disclaimer

This article was written about products for which Microsoft no longer offers support. Therefore, this article is offered "as is" and will no longer be updated.

Back to the top