This appendix gives a thumbnail view of the ADO.NET providers discussed in this book. It also describes where you can find some additional ADO.NET providers, including ODBC .NET, Oracle .NET, ODP.NET, and SQLXML. All these providers are freely downloadable. (Version 1.1 of the .NET Framework SDK includes ODBC .NET and Oracle .NET).
If you can't locate a managed provider for your data source, the next best option is to use an OLE DB driver with the .NET OLE DB provider classes. If your data source doesn't provide an OLE DB driver, your final resort is to use a lower-level ODBC driver in conjunction with the ODBC .NET provider. Many data sources, and nearly all database products include an OLE DB or ODBC driver.