Relationship between entity and relation in ER model and relational model? -


can set relation between entity , many many relationship on er model? if so, how represent it?

i read er data model (connecting 2 relations) speaks relational model...

in case have supermarkets db. speak entities problem:
-supermarket sells product.
-product sold on supermarket.
-a supermarket sells (0, n) product , product sold on (0, n) supermarket : many many relationship. price relationship attribute.
-user adds price product on specific supermarket.

so can add relationship between user entity , sells relationship? how represent on er model?

if not should set relationship between supermarket , price (in case weak entity: needs supermarket identifier) , relationship between price (weak entity) , supermarket (strong entity).

thanks in advance.

well, think have found solution. there 2 choices:
1.- ternary relationship between user, supermarket , product.
2.- in example in picture attached:enter image description here


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