Choose one of the relations example s and include as foreign key in s the primary key of t.įirst convert each entity and relationship to tables. So it is 11 cardinality with full participation constraint from passport. It is better to choose on entity total participation on s and include descriptive attribute. The er diagram represents the conceptual level of database design meanwhile the relational schema is the logical level for the database design. Er model to relational model entity and its attributes. In a simple relational database implementation each row of a table represents one instance of an entity type and each field in a table represents an attribute type. The Relational Model The er model is intended as a description of real world entities.Įr diagram to relational model. Binary relationship with 11 cardinality with total participation of an entity a person has 0 or 1 passport number and passport is always owned by 1 person. Although it is constructed in such a way as to allow easy translation to the relational schema model this is not an entirely trivial process.
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