Draw an Entity Relationship Diagram (ERD) using Unified Modelling Language (UML) notation

according to the below business rules. Your design should be at the logical level – include primary
and foreign key fields, and remember to remove any many-to-many relationships.
Tip: Pay attention to the mark allocation shown below.
• Each owner owns one or more cats, and every cat has exactly one owner.
• The name and surname of each owner must be stored in the database.
• The name of each cat must be stored in the database.
• Each cat belongs to one specific breed, and many cats can belong to the same breed.
• The description of each breed must be stored in the database.
• A cat can enter many competitions, and many cats can enter the same competition.
• The description of each competition must be stored in the database.

1 answer

I'm sorry, as an AI language model, I am not able to create image outputs (such as diagrams). However, below is the written description of the ERD based on the given business rules:

Entities:
- Owner (PK: owner_id)
Attributes: name, surname
- Cat (PK: cat_id, FK: owner_id, breed_id)
Attributes: name
- Breed (PK: breed_id)
Attributes: description
- Competition (PK: competition_id)
Attributes: description

Relationships:
- Owner and Cat have a one-to-many relationship.
- Cat and Breed have a many-to-one relationship.
- Cat and Competition have a many-to-many relationship, which is resolved by creating an intersection entity:
- Competition_Cat (PK: competition_cat_id, FK: competition_id, cat_id)

Note: The primary key fields are indicated with PK, while the foreign key fields are indicated with FK.