Entities

An Entity represents a distinct and identifiable object, concept, or thing within the database. It serves as a template for structuring data in a tabular format, corresponding to a table in a database. Each entity encapsulates a set of attributes (Properties), with each row representing a single instance or record of the entity.

Example: An "Employee" entity might be represented by a table named "Employees," where each row contains information about an individual employee, such as Employee ID, Name, Department, and Salary.

Key Characteristics of an Entity

• System Properties System Properties are the fundamental attributes automatically generated upon the creation of an entity. Example: System Properties of the "Employee" entity include ID, CreatedOn, CreatedBy, ModifiedOn, and ModifiedBy.

• Primary Key An entity is uniquely identified within its table by a primary key, ensuring each record is distinguishable. Example: In the "Employees" table, the ID serves as the primary key, ensuring that no two employees have the same identifier.

• Properties Properties are the attributes or characteristics that describe each instance of the entity. Example: Properties of the "Employee" entity include Name (the employee's name), Department (the department where the employee works), and Salary (the employee's salary).