Entity Relationship Diagrams (ERD)

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Match the following ERD model types with their descriptions:

Conceptual ERD = Most abstraction, used by business analysts for large projects Logical ERD = Adds more detail by defining operational and transactional entities Physical ERD = Actual design/blueprint with technical details including cardinality Cardinality = Specifies the numerical attribute of the relationship between entities

Match the following terms with their definitions:

Ordinality = Describes the relationship as mandatory or optional Conceptual ERD = General, high-level view of database design Logical ERD = Model that defines additional operational entities Physical ERD = Actual database design with many technical details

Match the following concepts with their explanations:

Cardinality = Specifies maximum number of relationships Ordinality = Specifies minimum number of relationships Conceptual ERD = Abstraction with least detail, suitable for large projects Physical ERD = Detailed design including primary and foreign keys

What is cardinality in the context of ERD symbols?

Cardinality specifies the numerical attribute of the relationship between entities. Signup and view all the answers

How does ordinality differ from cardinality in ERD modeling?

Ordinality describes the relationship as either mandatory or optional, whereas cardinality specifies the occurrences of a relationship. Signup and view all the answers

What is the main characteristic of a Conceptual ERD or data model?

Conceptual ERD provides the most abstraction and least amount of detail, suitable for large projects requiring a high-level view for business analysts. Signup and view all the answers

How does a Logical ERD differ from a Conceptual ERD?

Logical ERD adds more detail by defining operational and transactional entities, moving beyond the abstraction of a Conceptual ERD. Signup and view all the answers

What is the purpose of a Physical ERD or data model?

Physical ERD serves as the actual design or blueprint of the database, including technical details like cardinalities and primary/foreign keys. Signup and view all the answers

Describe the relationship between ordinality and cardinality in ERD modeling.

Ordinality specifies the minimum number of relationships, while cardinality specifies the maximum number of relationships. Signup and view all the answers

Why is a Conceptual ERD suitable for large projects according to the text?

Conceptual ERD offers a high-level, abstract view that is ideal for business analysts working on large projects. Signup and view all the answers

What type of entities does a Logical ERD define beyond a Conceptual ERD?

Logical ERD defines operational and transactional entities that are not included in the Conceptual ERD. Signup and view all the answers

How does a Physical ERD differ from a Logical ERD?

Physical ERD serves as the blueprint of the database, including technical details, while Logical ERD focuses on defining operational entities. Signup and view all the answers

What details are included in a Physical ERD that are absent in a Conceptual ERD?

Physical ERD includes technical details like cardinalities and primary/foreign keys, which are not present in a Conceptual ERD. Signup and view all the answers