Symptoms
Consider the following scenario:
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You have some Relational Online Analytical Processing (ROLAP) partitions in a Microsoft SQL Server 2008 R2 Analysis Services (SSAS 2008 R2) cube.
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You run a Multidimensional Expressions (MDX) query against the ROLAP partitions. Therefore, some ROLAP queries are sent to SQL Server.
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An error occurs during evaluation of an MDX query, and the processing task for the MDX query freezes. For example, SQL Server returns the following error message on the ROLAP queries:
The transaction active in this session has been committed or aborted by another session
In this scenario, no transactions can be committed, and you cannot connect to SSAS.
Cause
The issue occurs because, when ROLAP queries are sent to SQL Server and the queries fail with an error, a child thread of the MDX query stops running in SSAS. However, the main query thread is still waiting for the child thread. Therefore, the main thread blocks processing commit, and this blocks security evaluation for all new user sessions.
Resolution
The issue was first fixed in the following cumulative update of SQL Server.
Cumulative Update 12 for SQL Server 2008 R2 SP2 /en-us/help/2938478
Each new cumulative update for SQL Server contains all the hotfixes and all the security fixes that were included with the previous cumulative update. Check out the latest cumulative updates for SQL Server:
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. If the hotfix is available for download, there is a "Hotfix Download Available" section at the top of this Knowledge Base article. If this section does not appear, submit a request to Microsoft Customer Service and Support to obtain the hotfix. Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft website:
http://support.microsoft.com/contactus/?ws=supportNote The "Hotfix Download Available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
