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The difference between an associative entity and an attribute of associative relations?

What is the difference between an associative entity and an attribute of associative relations? In my book, Modern Database Management (Hoffer, 11th edition), the author argues that there is a difference between the two. Although, in fact, this does not explain why there is a difference, but simply gives examples of how they differ.

From what I'm collecting, the relation associated with this single attribute is an associative attribute and is indicated by a dotted line with a rounded rectangle with this attribute inside this rectangle. Whereas an associative object is more than one attribute describing a relationship. Both can only be used for many-to-many relationships in an ER diagram. Is my thinking process right?

Change Also, I forgot to mention that with associative objects, they also have an attribute that is a unique identifier, at least that's what I think.

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ER M: N , . , , - . , :

1-all the relationships for the participating entity types are M:N relationships 

2-the resulting associative entity type has independent meaning to the end user and has an identifier 

3- the entity has one or more attributes 

4-the entity participates in 1 or more relationships independent of the entities related in the associated relationship.
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An - , .

, - .

. , .

User
----
User ID
User Login Name
User Name
User Password

Permission
----------
Permission ID
Permission Name
Permission Description

, . , .

, .

UserPermission
--------------
User ID
Permission ID
Permission Granted Time Stamp

, , . User Permission. .

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