Users' questions

What is aggregation EER model?

What is aggregation EER model?

Aggregation represents relationship between a whole object and its component. Using aggregation we can express relationship among relationships. Aggregation shows ‘has-a’ or ‘is-part-of’ relationship between entities where one represents the ‘whole’ and other ‘part’.

What aggregation feature is missing from EER model?

Missing feature: In the EER (Enhanced Entity Relationship) model may not be used explicitly and it includes the possibility of combining the objects which are related to specific instance into a higher level aggregate object.

What is EER model explain in detail?

EER is a high-level data model that incorporates the extensions to the original ER model. Enhanced ERD are high level models that represent the requirements and complexities of complex database. In addition to ER model concepts EE-R includes − Subclasses and Super classes. Specialization and Generalization.

What is EER Modelling in DBMS?

The enhanced entity–relationship (EER) model (or extended entity–relationship model) in computer science is a high-level or conceptual data model incorporating extensions to the original entity–relationship (ER) model, used in the design of databases.

What does EER stand for in data model?

EER is a high-level data model that incorporates the extensions to the original ER model. These concepts are used when the comes in EER schema and the resulting schema diagrams called as EER Diagrams.

How to use aggregation in an E-R diagram?

Figure 2.21 shows the E-R diagram with aggregation. Transforming an E-R diagram with aggregation into tabular form is easy. We create a table for each entity and relationship set as before. The table for relationship set uses contains a column for each attribute in the primary key of machinery and work .

What is an extended entity relationship ( EER ) model?

Extended Entity-Relationship (EE-R) Model. EER is a high-level data model that incorporates the extensions to the original ER model. Enhanced ERD are high level models that represent the requirements and complexities of complex database. Subclasses and Super classes.

What’s the difference between EER and enhanced ERD?

EER is a high-level data model that incorporates the extensions to the original ER model. Enhanced ERD are high level models that represent the requirements and complexities of complex database. In addition to ER model concepts EE-R includes − Subclasses and Super classes.