In order to visually represent our tables (before even creating the SQL for our tables) we can use something called UML. UML stands for Unified Modeling Language. It can be used to visually represent for example classes, tables or use cases.

Couple examples of UML diagrams

As the old proverb says a picture is worth a thousand words, I will introduce a few examples of UML diagrams.

View of a Deployed System

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Restaurant Use Case Diagram

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Relational Database Example 1

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Relational Database Example 2

ERD

There also exists much more database-specific and stricter way compared to UML to draw and define the relationships called ERD. ERD stands for Entity Relationship Diagram. As this course is not strictly about database design, we will not cover this topic. But below you can find couple links about this topic, should you be interested in it:

• lucidchart.com/pages/er-diagrams
• visual-paradigm.com/guide/data-modeling/what-is-entity-relationship-diagram/