You can access external data tables in three ways: by linking the table to a Microsoft Jet database; by opening the table directly; or by importing the data in the table into a Microsoft Jet database table. The answers to the following questions will determine the data access method you choose:
If you need to maintain access to the data from another application, such as the native application used to create the database, you should link or open the external table rather than import the data. All of the IISAM drivers provide import or export capabilities.
If the table you want to access resides on an ODBC data source and you are not creating a client application where queries will be executed on the server, then the best performance will occur when you link the table rather than attempt to open it directly.
If you need frequent access to the data source, use a link, because linked tables maintain all connection information between sessions. If you only need occasional access to the data source, you can reduce the size of your Microsoft Jet database by opening the external table directly in code rather than storing the connection information in a link. If you need to access the data source only one time to migrate the data to Microsoft Jet format, use the import capabilities of the IISAM driver (if available).
See Also For information about how to access external data through ODBC and how to use ODBCDirect, see Chapter 9, “Developing Client/Server Applications.”