A Non-Relational Representation
To solve the problems from the relational model, the vehicle manufacturer example can be represented by a non-relational model which supports the following three properties:
- Type declarations are as flexible as in programming languages.
- Referencing: Objects can be uniquely identified independently of their attribute values.
- Reuse of information is possible by
- Aggregation: New objects are built out of existing ones.
- Specialization: It allows inheritance of structure and behavior.
Below shows how the entities are redefined by using a non-relational representation.
Persons
This entity has a name, age and domicile, and possesses a private fleet.
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⇒ |
Person: [
Name: String,
Age: Integer,
Domicile: Address,
Fleet: { Vehicle } ]
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Employees
It is with specific qualifications, salary, and family members.
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⇒
inheritance |
Employee is-a Person: [
Qualifications: { String },
Salary: Integer,
Familymember: { Person } ]
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Each employee specializes a person. By means of inheritance, the structure of persons is reused for employees.