Semantics of DBGUID_DEFAULT
OLE DB defines a special language dialect identifier, DBGUID_DEFAULT, that denotes the default language dialect. In the context of OLE DB for OLAP, the following semantics apply to the use of this identifier:
If the provider is both a TDP and an MDP, it must interpret the command string as SQL when DBGUID_DEFAULT is passed as the dialect identifier.
If the provider is an MDP, it must interpret the command string as MDX when DBGUID_DEFAULT is passed as the dialect identifier.
Note
Multidimensional consumers are strongly discouraged from using DBGUID_DEFAULT for creating datasets. They should use DBGUID_MDX instead.