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Extended Entity-Relationship Diagram: Do the sub classes have foreign keys or primary keys? - Database Administrators Stack Exchange
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Database — Modeling : Entity Relationship Diagram (ERD) (Part 5) | by Omar Elgabry | OmarElgabry's Blog | Medium
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3. The wikiGIS Entity-Relationship Diagram ([PK] – Primary Key, [FK] –... | Download Scientific Diagram
![Database — Modeling : Entity Relationship Diagram (ERD) (Part 5) | by Omar Elgabry | OmarElgabry's Blog | Medium Database — Modeling : Entity Relationship Diagram (ERD) (Part 5) | by Omar Elgabry | OmarElgabry's Blog | Medium](https://miro.medium.com/max/1168/1*QkIeA-uwU244QoG0jF3FBg.png)
Database — Modeling : Entity Relationship Diagram (ERD) (Part 5) | by Omar Elgabry | OmarElgabry's Blog | Medium
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