Attributes of Relationship Types
Explore how attributes can be assigned to relationship types in the Entity-Relationship model. This lesson helps you understand when to associate attributes with entities or with relationships based on different relationship cardinalities, enhancing your ability to design efficient and clear database schemas.
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Attributes of relationship types
Relationship types can also have attributes, similar to those of entity types. Hence the relationship WORKS_ON between EMPLOYEE and PROJECT has an attribute Start_Date. This is illustrated in the diagram below:
Generally, it is not recommended to give attributes to relationships if it’s not required because when we represent this ER diagram in the database, we don’t want to create a separate table for each relationship with attributes as this ...