This help book in the Language Reference book covers the following information:

Data objects provide access to database tables and are used to link tables to the user interface.

The Borland Database Engine (BDE) considers the DBF (dBASE/FoxPro) and DB (Paradox) tables types as Standard tables. The BDE can access any Standard table directly through its path and file name, without having to use a BDE alias.

All other table types, including InterBase, Oracle, Microsoft SQL Server, Sybase, Informix, and any ODBC connection, require the creation of a BDE alias through the BDE Administrator. You may also create a BDE alias to access Standard tables. In that case, the alias specifies the directory in which the tables exist; the database consists of the Standard tables in that directory, and you may not open any others from another directory unless you explicitly specify the full path without the alias. See class Database.

All tables, whether or not they require a BDE alias, are accessed through SQL and the data objects.