BeginSession Element (XMLA)
Uses a SOAP header in a SOAP request message to start a new session on an instance of Microsoft SQL Server Analysis Services.
The BeginSession header element is part of a SOAP request sent to an Analysis Services instance, and explicitly starts a new session on the instance. The SOAP header returned by the SOAP response contains a Session element that identifies the new session. This new session identifier be stored and sent in subsequent SOAP requests using the Session header element.
If the BeginSession header element is not sent, a session is not explicitly started. If a session is not explicitly started, transactions on that session cannot be managed. In other words, you cannot use the following XML for Analysis (XMLA) commands: BeginTransaction, CommitTransaction, and RollbackTransaction. All XMLA methods and commands executed on an implicitly started session are considered to be atomic transactions.