Some notational systems exist that can help you develop and record data models. Bachman, Chen, Martin, and other data-modeling gurus each have their own methodology and notation. While all you need to produce these diagrams is paper and a pencil, most modelers opt for a modeling tool, frequently referred to as a CASE tool. Modeling tools make extensive use of graphical interfaces and visual editing to produce model diagrams. Pop-up forms capture the necessary names and definitions.
Definitions produce a data dictionary.
You can produce reports to review with business users to validate and refine the definitions. If a tool can produce DDL automatically, the dictionary also includes physical design characteristics, such as volumes, domains, and indexes. Most tools that support ER modeling also provide rule-checking to make sure the models produced are valid. These tools check for violations to the rules of normalization and flag the absence of primary keys or the inappropriate use of foreign keys. Since an analyst develops the model interactively, this feedback allows him or her to catch errors at once rather than their being perpetuated into lower-level models.