1. Customer and product.
Identify the entities and their attributes
Identify the degree of their relationship
Identify their cardinalities
Constraints
Draw the ERD
Entities:
1. Customer
- Attributes: customer_id, name, email, phone
2. Product
- Attributes: product_id, name, description, price
Relationship:
The relationship between Customer and Product is a Many-to-Many relationship.
Cardinalities:
- Each Customer can purchase multiple Products.
- Each Product can be purchased by multiple Customers.
Constraints:
- A Customer must be linked to at least one Product.
- A Product must be linked to at least one Customer.
ERD Diagram:
```
+--------------+ +--------------+
| Customer | | Product |
+--------------+ +--------------+
| customer_id | <-----> | product_id |
| name | | name |
| email | | description |
| phone | | price |
+--------------+ +--------------+
```
Note: The relationship between Customer and Product will typically require an intermediate entity (e.g., Order) to represent the actual purchases made by customers. However, as the prompt only asks for the entities and their attributes, the intermediate entity is omitted from the diagram.
To identify the entities and their attributes, we need more information about the specific customer and product scenario you are referring to. However, here is a generic example to demonstrate the process:
Entities and Attributes:
1. Customer entity:
- Attributes: CustomerID, Name, Address, Phone, Email
2. Product entity:
- Attributes: ProductID, Name, Description, Price, Quantity
Degree of Relationship:
Again, to determine the degree of the relationship between customer and product, we need more context. Here are some possible options:
- If a customer can purchase multiple products, and a product can be purchased by multiple customers, then the degree would be a Many-to-Many relationship.
- If a customer can purchase multiple products, but a product can only be purchased by one customer, then the degree would be a One-to-Many relationship.
- If a customer can only purchase one product, and a product can only be purchased by one customer, then the degree would be a One-to-One relationship.
Cardinalities:
To determine the cardinalities, we need to know the specific rules or constraints of the scenario you are referring to. For example:
- If a customer can purchase multiple products and a product can be purchased by multiple customers, the cardinality would be Many-to-Many.
- If a customer can purchase multiple products, but a product can only be purchased by one customer, the cardinality would be One-to-Many.
- If a customer can only purchase one product, and a product can only be purchased by one customer, the cardinality would be One-to-One.
Constraints:
Constraints could include rules such as:
- A customer must have a unique CustomerID.
- A product must have a unique ProductID.
- The price attribute of the product should not be negative.
- The quantity attribute of the product should not be negative.
Drawing the ERD:
Based on the information provided above, you can now draw an Entity-Relationship Diagram (ERD) to visualize the relationships between the entities and their attributes.