AcuXDBC relies on Extended File Descriptors (XFDs) to map your COBOL data items to database columns. An XFD file may be created either as a simple text file or as an XML file. In either case, the XFD contains a description of a COBOL indexed, sequential, or relative file based on its fields. XFDs are automatically generated when you compile your program with the -Fx option. If the default mapping is sufficient, there is nothing more you need to do to prepare your COBOL for AcuXDBC except create the XFDs themselves. See The Role of XFDs for information on creating XFDs.
If you want to add more detail to your database tables, you can add other directives to your program before generating the XFDs. Directives are optional comments that you can place into a File Descriptor (FD) in your COBOL source code to control how XFDs are built. See Using XFD Directives for information on adding directives.