![]() To create the offering entity type, drag the entity icon to the canvas and rename it as offering. The canvas shows the course entity type with course number as the primary key, and attributes course description and course units. ![]() Click the add button again and type course units with smallint as a data type. Click the add button again and type course description as a name, varchar as a data type, and 200 as a length. Type course numbers as a name, select the primary key checkbox, chars a data type and type 10 as the length. In the columns tab, use the add button to open the attributes specification window. Change the entity name to course, then I will create attributes for course, right-click on the course entity type and select the open specification button to open the entity specification window. Now I will create the course entity type, drag the entity icon in the toolbar to the drawing canvas. Right-click on the drawing name to rename it as university database ERD. Visual paradigm shows a blank canvas with diagram and drawing icons in the toolbar on the left. Let's begin by opening visual paradigm with no active diagram. With this background, we are now ready to create an ERD using visual paradigm. In contrast, the course notation uses diagonal lines in the corners of rectangles to denote weak entity types. Visual paradigm uses the same notation for regular and weak entity types. For example, the Has relationship uses just a single perpendicular line showing a mandatory relationship, in contrast the course notation uses two perpendicular lines denoting one for the minimum and maximum cardinality. Visual paradigm provides an abbreviated notation for mandatory relationships with a minimum and maximum cardinality of one. For example the enrollment entity type contains foreign keys for student number and offer number, in addition to one-to-many relationships registers and grants. Visual paradigm shows foreign keys in contrast to the course notation that does not show foreign keys. Before demonstrating construction of the university database ERD, I will briefly depict differences in notation between visual paradigm in a course notes. In addition, I will demonstrate simple documentation features of visual paradigm. In the demonstration, I will create the course in offering, entity types, the Has relationship, the identification dependency, enrollment along with the grants and registers relationships, in the supervisor's self-referencing relationship. This demonstration uses the university database ERD, presented in module 6 and 7. For commercial usage visual paradigm provide subscription editions with many other features for other types of diagrams, software development, project management, business modeling, co-generation, and many more features. This demonstration uses the community edition visual paradigm, supporting diagrams for data modeling, software development in a unified modeling language. ![]() I encourage you to use visual paradigm for experience with a commercial grade tool for database development. Although the crow's foot notation supported by visual paradigm differ slightly from the notation used in the course, you can use visual paradigm for data modeling assignments. This demonstration depicts basic features of visual paradigm, a powerful tool for database in software development. ![]()
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