Data Modeling encompasses the final design and build stage of a project. This consists of iterations of the analysis stage, refining the analysis model and the Data Model. The Data Model describes how storage information can be recorded in the dictionary and displayed on a diagram. This information can also be mapped onto a database structure.

You use a Table Relationships Diagram to specify the physical implementation of classes. The Table Relationships Diagram supports a relational database structure and you can specify tables, columns, indexes and relationships for the classes that you have modeled in Modeler.

A database contains a number of tables, but is not displayed on the Table Relationships Diagram. A table, the equivalent of a class, consists of a series of columns, the equivalent of attributes. Within the table, each column must be unique. The table is accessed through its prime key, which is made up of one or more column names. You can use indexes to specify secondary access keys to the table, together with relationships to specify links to other tables. Relationships are implemented as foreign keys.

Modeler contains a storage mapping function which allows you to automatically create tables, columns and relationships from information contained in a Class Model. The tables can then be automatically drawn onto a Table Relationships Diagram.

The Table Relationships Diagram is used to show RDBMS table, column and relation details. It is a logical data structure diagram, as opposed to a physical data structure diagram which reflects physical DBMS specific characteristics (for example, compare Oracle and Ingres).

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