Can I use a ternary relationship as an associative entity?

Question

I want to know whether I can connect a ternary relationship to a another entity without that forming an n-ary relationship. To describe in terms of tables, I want to get a reference in the ternary relationship table to another (entity's) table.

Answer 1

Conceptually and generally, yes.

It can reasonably be called a binary relationship between the other and the associative entity, and a 4-way relationship among/over the other and the entities that form the associative entity.

But what exactly your terms mean and how you are allowed to design depends on your particular information modeling method and/or tool.

Eg your method/tool might or might not require that you add an identifier to an association type and use that in other tables rather than just the 3 columns.

Eg E-R Modeling distinguishes between "entity" and "relationship" types (each type having a corresponding table with other columns for "properties"). But this isn't actually necessary in informaton modeling since an "entity" could just be considered a 1-ary "association" and a "property" could just be considered an "entity". (Is a "marriage" a "relationship" between spouses and/or an "entity" with an anniversary and/or "property" of a family or wedding?) Also, any columns that are unique in any table or query result identify some "thing" type whether or not it is one of the base (non-associative or associative) "entity" types.

(More here.)