Use Domains in SQL Developer Data Modeler
How long is an email address? 30 characters should be enough, I thought. And I was right for about three weeks or so until one of the smartest Oracle experts in Europe tried to submit an abstract at our call for paper site . His email address had 32 chars and therefore failed already at registration. A bit embarrassing. The data model was created in SQL Developer Data Modeler (SDDM) and I had done something right. In the data model EMAIL was defined as a domain and not simply as VARCHAR2(30) in different places in the data model. ...