What are the benefits or disadvantages of ER diagrams
- Conceptual simplicity. If relationships between entities and attributes are known, an ERD can be quickly drawn.
- Explicit visual representation. The database structure can be easily comprehended after consulting the diagram.
- Communication effectiveness.
- Immense flexibility.
The main difference between Logical and Physical Data Model is that Logical data models help to define the data elements and their relationships, while the physical data models help to design the actual database based on the requirements gathered during the logical data modelling.
What are the benefits or disadvantages of ER diagrams? Why bother with logical design and not just create tables andcolumns (physical design) directly?