What is the example of ER model?
Examples: an employee entity might have a Social Security Number (SSN) attribute, while a proved relationship may have a date attribute. All entities except weak entities must have a minimal set of uniquely identifying attributes which may be used as a unique/primary key.
What is ER model in DBMS with example?
ER diagram basically having three components: Entities − It is a real-world thing which can be a person, place, or even a concept. For Example: Department, Admin, Courses, Teachers, Students, Building, etc are some of the entities of a School Management System.
What is ER modeling used for?
Database design: ER diagrams are used to model and design relational databases, in terms of logic and business rules (in a logical data model) and in terms of the specific technology to be implemented (in a physical data model.)
Which of the following is an example of a use of an ER diagram?
ER model is used to represent real life scenarios as entities. The properties of these entities are their attributes in the ER diagram and their connections are shown in the form of relationships.
Which of the following is example of object based logical model?
Discussion Forum
| Que. | Which of the following is example of Object based logical model? |
|---|---|
| b. | Hierarchical Model |
| c. | Relational Model |
| d. | Network Model |
| Answer:Entity Relationship Model |
What are the components of ER diagram explain with an example?
ER diagrams or ERD’s are composed of three main elements: entities, attributes, and relationships. Entities – typically displayed in a rectangle, entities can be represented by objects, persons, concepts, or events that contain data.
What are the features of ER model in DBMS?
There are three basic elements in an ER Diagram: entity, attribute, relationship. There are more elements which are based on the main elements. They are weak entity, multi valued attribute, derived attribute, weak relationship, and recursive relationship.
What two concepts are ER Modelling based on?
ER modelling is based on two concepts: Entities, defined as tables that hold specific information (data) Relationships, defined as the associations or interactions between entities.
What role ER model plays in the database design process?
1. What role does the ER diagram play in the design process? A completed ER diagram is the actual blueprint of the database. Its composition must reflect an organization’s operations accurately if the database is to meet that organization’s data requirements.