The Microsoft SQL Server .NET
data provider is recommended for all
applications using Microsoft SQL Server 7.0 or later, or Microsoft
Data Engine (MSDE) applications.
The Microsoft OLE DB .NET data provider is
recommended for applications using Microsoft SQL Server 6.5 and
earlier with the OLE DB provider for SQL Server (SQLOLEDB). It is
also recommended for applications using Microsoft Access databases.
Additionally, it can access any data source that has an OLE DB
provider that supports OLE DB interface greater than Version 2.5.
However, if a data source-specific provider is available, that is
likely to be a preferred solution.
The ODBC .NET data provider can be used
for any data source that is accessible through ODBC but
doesn't have either a .NET data provider, an OLE DB
provider, or a vendor-supplied .NET data provider.