Question

give main components of ER​

Answer 1

Answer:

https://whatisdbms.com/e-r-diagrams-in-dbms-components-symbols-and-notations/

E-R Diagrams in DBMS: Components, Symbols, And Notations

Answer 2

Answer:

Entities, which are objects or concepts that can have data stored about them. ...

Attributes, which are properties or characteristics of entities. ...

The relationships between and among those entities.

Actions, which describe how entities share information in the database.

Connecting lines.