Data Modeling with ER Model - Technical MCQs

Q1:

Which type of entity cannot exist in the database unless another type of entity also exists in the database, but does not require that the identifier of that other entity be included as part of its own identifier?

A Weak entity

B Strong entity

C ID-dependent entity

D ID- independent entity

ANS:A - Weak entity

A weak entity can have a partial key but it doesn't uniquely identify it, so it needs the primary key of its strong entity too.