CSS SQL Server Engineers

We have a few customers who reported that some of their queries run slower following upgrade from SQL Server 2000 to SQL Sever 2005, 2008 and 2008 R2. Specifically, queries experiencing the issue have anti-semi joins in the query plan and the join involves...

Technorati Tags: Performance Frequently, we see our customers using table variables in their stored procedures and batches and experience performance problems.   In general, these performance problems are introduced because of large number of...

In June I introduced you to a new Best Practices Analyzer for SQL Server, SQL Server 2008 R2 BPA: http://blogs.msdn.com/b/psssql/archive/2010/06/20/introducing-the-sql-server-2008-r2-best-practices-analyzer-bpa.aspx I’ve seen some mixed reaction to this...

I would love nothing more than to take you back to my high-school days running the 440 yard hurdles (yes yards not meters) where timing was done with a stop watch (you know the old, moving dial style) but timers on the PC don't allow that simplicity....

I ran into an issue which has some aspects I found interesting and thought you might as well. When you do a select against the sys.messages virtual table the data is retrieved from the resource files (.RLL) files stored under <<Instance>>...

From: Robert Dorr Sent: Friday, August 13, 2010 8:58 AM Subject: RE: SQL Server Trace Replay - "Replay Result Set Event" The Result Set event is one of several client side replay events. Here are some of Common Result Event Columns Text Returned values...

I was working on a customer issue which involved debugging a dump.  The dump was generated via SQLDumper within Reporting Services.  So, the name of the dump was similar to SQLDmpr0001.mdmp.  When I opened the dump I saw the following:...

This message has come across my desk a couple of times in the last week and when that happens I like to produce blog content. The error is when you are trying to use a pooled connection and the reset of the connection state encounters an error. Additional...

Recently a customer ran into an issue where they had successfully installed SQL Server 2008 SP1 on a 2 node Windows 2008 cluster. When they went to restore a database that was given to them, they found out the database was created with the new SQL 2008...

Today I ran into an issue where, SQL Server 2008 SP1 was installed on a Windows 2008 cluster and was working just fine, but we wanted to install SQL Server Integration Services (SSIS) to the two nodes of the cluster. Since SSIS is not cluster aware, we...

There is a bug in SQL Server 2008 that causes PREEMPTIVE_OS_GETPROCADDRESS to include and accumulate the execution time of the extended stored procedure (XPROC) . The following is an example showing the increase in the GetProcAddress wait time. select...

  Recently I worked with a very knowledgable customer who called in and wanting to know things about statistics.  This is because he noticed that his query would get inaccurate cardinality estimate due to ‘inaccurate histogram.   ...

We get our fair share of cases related to SQL Server running ( or not running) on a Windows Cluster.  I had one of them recently where the customer was seeing different authentication modes for SQL Server depending on which node of the 2-node cluster...

In this post , I talked about how to use computed column to improve performance. By creating index on a computed columns, you can have two benefits. You get better cardinlaity esimate on the expression in your query and your query may also use that index...

Almost three years ago, I posted about why Reporting Services takes so long to respond to the first request if it has been sitting idle for a long time (like overnight).  The original post can be found at http://blogs.msdn.com/b/sqlblog/archive/2007...

I’ve had numerous questions regarding Kerberos, both internally within Microsoft and with Customers.  It continues to be a complicated topic and the documentation that is out there can be less than straight forward.  Based on some previous items...

After getting through the Pre-Reqs for BPA (PowerShell 2.0, MBCA, .NET Framework), you may hit one of two scenarios when installing BPA. In all of the cases of an install failure, you will see the following error: “There is a problem with this Windows...

Some of you may have noticed I haven’t posted a blog in some time. Well, I’ve been a bit busy working behind the scenes on a new tool we released this weekend, the SQL Server 2008 R2 Best Practices Analyzer (BPA). You may remember that I announced this...

We recently worked with a customer who ran into an interesting situation. This problem deals with SQL Server 2005 Service Pack 3 setup. Normally, when you launch the SQL 2005 SP3 setup and you reach the screen which shows the components for which you...

I encountered another interesting research issue to share with you. The documentation states RecordsAffected are for INSERT, UPDATE and DELETE but it might fool you. ------------------------------------------------------------------------------------...

The short answer is that it is not an error and the message should be a WARNING. I looked at the latest, internal code base it has already been changed to a WARNING. if (!DeviceIoControl (volume, IOCTL_DISK_GET_CACHE_INFORMATION, NULL, 0, &m_diskCacheInfo...

A question arose asking - "What does the LPE_BATCH spinlock type represent?" You can see the LPE_* series of spinlocks using the DMV query " select * from sys . dm_os_spinlock_stats " A spinlock is a lightweight, user mode synchronization object used...

You know how every product that has an underlying database has documentation that says not to modify the schema?  Do you always pay attention to that warning? If your product is Reporting Services, I just ran into a case today which I hope convinces...

In 2002 the SQLOS team added specific checks for non-yielding scheduler issues. You may be familiar with the 178** series of errors like 17883 scheduler non-yield. Since 2002 the test matrix for SQL Server has flagged these errors and corrected them....

I am still working to resolve the customers problem but during my investigation I briefly looked a the SQLAgent logging format and thought you all might like some of these details. From: Robert Dorr Sent: Monday, May 24, 2010 9:47 AM Subject: RE: SPID...