Microsoft® SQL Server™ OLAP Services supports SQL queries or clauses in the following situations:
OLAP Services is both a multidimensional data provider (MDP) and a tabular data provider (TDP). Therefore, executing an SQL query returns either a multidimensional dataset or a flattened rowset, depending on the query language dialect used. OLAP Services recognizes both the SQL dialect and the multidimensional expressions (MDX) extensions. For more information, see the OLE DB 2.0 and later documentation.