Explain the component modules of DBMS & their interactions with diagram

Explain the component modules of DBMS & their interactions with diagram

Answer:-

In the Entity-Relationship (ER) model, attributes describe the properties or characteristics of entities or relationships. There are several types of attributes based on their nature and structure.

Types of Attributes in ER Model

1. Simple (Atomic) Attribute

• Cannot be divided further.
• Represent a single value.
• Example: Name, Age, Salary

2. Composite Attribute

• Can be divided into smaller sub-parts.
• Sub-parts are meaningful on their own.
• Example:
  FullName → can be split into FirstName, LastName
Address → can be split into Street, City, Zip

3. Derived Attribute

• Not stored in the database directly.
• Can be calculated from other attributes.
• Example:
  Age can be derived from DateOfBirth
TotalPrice from Quantity × UnitPrice

4. Multi-Valued Attribute

• Can have multiple values for a single entity.
• Usually shown as double ovals in ER diagrams.
• Example:
  A person may have multiple PhoneNumbers or EmailAddresses.

5. Key Attribute

• Used to uniquely identify an entity.
• It is part of the primary key.
• Example:
  RollNo for a student, EmployeeID for an employee

6. Single-Valued Attribute

• Holds only one value for a given entity.
• Example: DateOfBirth, Gender

✅ Summary Table