Programming interfaces have proliferated for accessing data sources from the Windows platform. Here are a few of those standards and brief descriptions. When I include sample code in this column, it's usually ActiveX Data Object, Multi-Dimensional (ADO-MD).
OLE DB: A high-performance, COM-based data-access interface for relational data sources.
ActiveX Data Objects (ADO): A COM-based data-access interface that supports scripting languages such as VBScript. ADO is a layer on top of OLE DB and is the COM programming interface most programmers choose.
OLE DB for OLAP: An extension to OLE DB for accessing OLAP (multidimensional) data sources, this API supports MDX queries and multidimensional results. Microsoft will extend OLE DB for OLAP with SQL Server 2000 to support data-mining capabilities.
ActiveX Data Object, Multi-Dimensional (ADO MD): An extension to ADO for accessing OLAP (multidimensional) data sources. This interface supports scripting languages, such as VBScript, and is an API layer on top of OLE DB for OLAP.
OLE DB for Data Mining (DM): Like OLE DB for OLAP, OLE DB for DM is an extension of the standard OLE DB data-access API and is used for data mining of relational data sources.