Relationship Details in Database Static Structure
Relationship Details: Dominant Role: Optional in One to One scenario: None: Both entities generate foreign keys Entity A to Entity B: Only Entity B generates foreign key Entity A to Entity B: Cardinality: n, m indicates Entity A can correspond to n-m instances of Entity B, with options 0,1, 1,1, 0,n, and 1,n Dependent Relationship: Meaning: Each instance of A is identified by an instance of B in physical modeling impact: B's primary key becomes part of A's primary key and simultaneously a foreign key of B Mandatory Relationship: Meaning: Each instance of A requires an instance of B in physical modeling impact: The foreign key from A to B cannot be null in A
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