In the Heinemann textbook it says "An ERD is a graphical method of identifying the entities and showing the relationship between them. "
Cambridge says "An ERD is one type of schematic diagram. It maps entity types, the relationships between them and the characteristics of the relationships etween entity types."
The attachment that Makro posted looks like the one in the Heinemann textbook so I'd assume that it's correct.
cxlxoxk said:
Entity-relationship diagrams don't show single entities or single instances of relations. Rather, they show entity sets and relationship sets. Example: a particular song is an entity. The collection of all songs in a database is an entity set.
I'm not sure this is true since my Cambridge book called the table 'headings' entities. Although I'm not sure how correct those books are >>
cxlxoxk said:
I think what it is saying there is that a ERD/Schema wouldn't show eg. "Chasing Cars" and " Snow Patrol"...it would show "song name" and "artist".
^^I agree with that though.