Generalization in DBMS

Generalization in DBMS

 

In this article, we will learn about Generalization in DBMS. We will understand the concept with examples and designing steps for Generalization.

Generalization is the term  used for the design process of any relational schema.

Generalization in DBMS

Generalization

Generalization is the term that is frequently used for the design process of any relational schema.

  • Definition: Generalization is a bottom-up design process in which two or more entities of lower level or combined to form a higher level entity if they have some common  attributes or properties.
  • In these two or more  entities integrated to form a generalized entity that sub-classes are combined to make a super-class.
  • Generalization is viewed as a Reverse process of specialization.
Example:

Student, teacher, workers, doctor,…….are generalized as person.

Design steps for Generalization

  • Define some entities with attributes.
  • Identify common attributes between these entities and create a super-entity, so that all the remaining entities in some way related to the super-entity.
  • Add Relationship between entities.

Examples for Generalization

  • For example, we have entities as a teacher, workers, students, households…so on.
  • These entities have some most common requirements name, salary, role, etc role of these categories can be generalized as a super common entity as citizens.

Conclusion:

  • Generalization is a bottom-up design approach.
  • Common properties from sub-entities are generalized to a super-entity.
  • generalization is always applied to a group of entities and if over-designed it seems to reduce the schema size.
Learn more about DBMS here on this page.