Hier werden die Unterschiede zwischen zwei Versionen angezeigt.
Beide Seiten der vorigen Revision Vorhergehende Überarbeitung Nächste Überarbeitung | Vorhergehende Überarbeitung |
modul:m290:learningunits:lu03:theorie:d_crowfeet [2024/08/16 11:19] – vdemir | modul:m290:learningunits:lu03:theorie:d_crowfeet [2024/10/02 15:14] (aktuell) – vdemir |
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====== LU03d - The Crow's Feet Notation ====== | ====== LU04d - The Crow's Feet Notation ====== |
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==== The Basics of Crow’s Foot Notation ==== | ==== The Basics of Crow’s Foot Notation ==== |
Consider a simple ERD for an online bookstore. The entities might include **Customers**, **Orders**, and **Books**. | Consider a simple ERD for an online bookstore. The entities might include **Customers**, **Orders**, and **Books**. |
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- **Customers** can place multiple **Orders** (One-to-Many). | * **Customers** can place multiple **Orders** (One-to-Many). |
- Each **Order** can include multiple **Books** (Many-to-Many). | * Each **Order** can include multiple **Books** (Many-to-Many). |
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Using Crow’s Foot notation: | Using Crow’s Foot notation: |
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- The relationship between **Customers** and **Orders** would have a single line connecting the entities with a vertical line on the **Customers** side and a crow’s foot on the **Orders** side. | * The relationship between **Customers** and **Orders** would have a single line connecting the entities with a vertical line on the **Customers** side and a crow’s foot on the **Orders** side. |
- The relationship between **Orders** and **Books** would have crow’s feet on both sides, representing the many-to-many relationship. | * The relationship between **Orders** and **Books** would have crow’s feet on both sides, representing the many-to-many relationship. |
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==== Vocabulary ==== | ==== Vocabulary ==== |