From your database design, you set up the data dictionary for the database. The data dictionary describes all the tables and fields used in your database. You create your database the database setup utility (MAKEDB). You can learn about how to design a DP4 database here.
You can use create a plan of all the tables on your database with the data dictionary planner.
DP4 automatically generates database structure information from your table definitions. The structure information includes the indexes used to find records, and the links between each table.