Aggregation in DBMS

Aggregation in DBMS

 

In this article, we will learn about Aggregation in DBMS.

  • Aggregation is a design strategy in which the relationship is modeled between a collection of entities and another relationship
  • Simply  it is used when we need Express a relationship among other relationships

Definition: Aggregation is a design process in which the relationship between two entities is treated as a single entity.

 

Aggregation in DBMS

Example:

In Real world situation for example if students visit a coaching institute then he shows interest not only to inquire about the course alone or not only just coaching  center, he will definitely enquire the details about both the coaching institute and the details of the concerned course

Design steps for aggregation 

  • Define entities and their attributes
  • Add a relationship between these entities
  • Define another entity so that the relationship can be established between the existing relationship and this entity

Why aggregation

  • Aggregation is a process of compiling information on an object thereby abstracting higher-level object
  • In SQL we need to find the sum of salaries of all the employees working in an organization or to find the highest-paid employee from all branches of the organization etc.
Learn more about DBMS here on this page.