The answer depends on who you asked the question. If you ask an Analysis Services member team he/she might answer XML DDL, MDX (Multidimensional Expressions). DMX (as in Data Minining Extensions and not DMX the rapper), XMLA (XML for Analysis), PMML (Predictive Model Markup Language), OLE DB for OLAP (ODBO), ADOMD, ADOMD.NET, DSO, AMO and SQL. Yes even SQL, or at least a subset of SQL.

You don't have to trust my words (SQL to talk to AS), here's the proof:

If you are reading Books Online then you find out that you use Analysis Services Scripting Language.

So many words can make thing that Analysis Services is too complicated but the truth is that is not Big Smile

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I just added another way here: Screencast - Exploring Analysis Services using PowerShell

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