Hello all,
I was wondering if there's somewhere good documentation of the semantics of isolation level in a data source in an Analysis Services project and how the different isolation levels affect the processing of Analysis Services database. I don't mean the semantics of differerent isolation levels in SQL server, those are well documented, but what the isolation level actually means in context of an Analysis Services data source.
I'm interested in using snapshot isolation level so that when processing the Analysis Services database all the data for the Analysis Services objects would be got using a snapshot of the SQL Server database. I wonder if this is possible. There's additionally the "Maximum number of connections"-property. I assume that when processing the Analysis Services multiple connections are made to SQL server and if each of those connections use snapshot isolation level, there's no guarantee the snapshots contain the same data.
My actual problem is that the data may change in the SQL server database while processing Analysis Services database. This causes Analysis Services processing failures sometimes, since a value in the database may be found in one dimension, but not in another one.
Any ideas?
r,
J
This doesn't directly answer your question, but it might be easier to support and maintain. Try setting a flag on the records in the data warehouse tables. The flag would indicate whether or not the record was available for upload into SSAS. The flag would be set to 1 (where it was currently set to 0) at the top of the run. Data entering the tables during the run would have the flag set to the default of 0. Your queries would have logic to select just those records with the flag set to 1.
Otherwise, you can follow the steps provided in this KB article to setup/configure/use snapshot isolation:
http://support.microsoft.com/kb/919160
Good luck,
Bryan
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