Concurrency Series: Common Concurrency Issues with Applications

As part of my role as a program manager in SQL Server Engine, one of the areas I am reponsible for is the concurrency related features in SQL Server. If you have been involved with database applications as a develeoper or as a DBA in keeping the application running, I am sure you will agree that blocking is one of the most… Read more

Minimal logging and MERGE statement

In my earlier blog http://blogs.msdn.com/b/sqlserverstorageengine/archive/2008/10/24/new-update-on-minimal-logging-for-sql-server-2008.aspx, we discussued how we can get minimal logging using TF-610 when using TSQL INSERT statement. Interestingly, you can get minimal logging when using MERGE statement as well. Here is a simple example to illustrate it. use bulktestgo alter database bulktest set recovery SIMPLE — enable the trace flag 610dbcc traceon… Read more

Backup compression and Virtual Device Interface (VDI)

People often ask if they can get native SQL Server backup compression using VDI interface. The simple answer is ‘yes’ but there are few things you need to be aware of as described below. You can get details on VDI by clicking link-to-VDI-Specifications. Within the VDI protocol, the backup application specifies a TSQL backup command.  This means that the backup application can use… Read more

Performance improvement by orders of magnitude when merging partitions in SQL Server 2008R2

I am publishing this Blog on behalf of Hermann Daeubler, our SAP expert Scenario: Let’s assume we have a table consisting of five partitions and the one in the middle needs to  be dropped. In SQL Server we need the following steps to accomplish this task a)      Create a non-partitioned target table with the same structure and… Read more

Improvement in minimizing lockhash key collisions in SQL Server 2008R2 and its impact on concurrency

Another improved functionality in SQL Server 2008 R2 I am posting this on behalf of Juergen Thomas who has been with SQL Server PM team from 12+ years and is an expert in SAP.  Juergen>> In this article I’d like to talk about another improvement we made to SQL Server 2008 R2. The improvement pretty… Read more