ER diagram

Question

Every weak entity has to be related to a strong entity through a strong relationship is this statement correct?'

Comments

Correct one is $\text{identifying relationship. }$

Answer 1

Weak Entity is an entity that can not identified(its mean does not have primary key)  by its own attribute alone so it need to relies on Strong Entity for its identification.

lets clear confusion of Weak & Strong Entity, Sometimes we confused between them.
lets take an example of order and customer, its seems like order is dependant on customer but order has there own order id and it will going to identify unique by there is order id.

Consulsion, It Weak Entity depands on Stong entity.
 

Comments

Consider a case Account (AccountNumber --> PK) {Strong entity}, Loan (AccountNumber+LoanNumber --> unique identifier ) {weak entity}, Payment (AccountNumber+LoanNumber+PaymentID --> unique identifier) {Weak entity} having a relationship like: Account <-- R1 == Loan <-- R2 == Payment.

In this case Payment being weak entity is dependent on Loan which is also a weak entity though Loan being weak entity is further related to Account which is a strong entity i.e. Payment is not directly related to Account.

There may exist a direct relation between Strong and Weak entity but in case of no direct relation there should exist an indirect relation.

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Every weak entity has to be related to a strong entity through a relationship but not necessarily a strong relationship so i think its Fasle