ER MODEL

Question

What is the relationship between strong entity and weak entity

1:1

1:M

M:1

M:N

Please explain ?

Comments

Selected answer is wrong. Check this by Arjun sir

https://gateoverflow.in/14043/what-is-the-relationship-between-weak-and-strong-entity

Answer 1

An entity set that does not have a primary key is referred to as a weak entity set. so the existence of a weak entity set depends on the existence of a strong entity set  so it should have one to many relationship.

Comments

Please explain why not many to many I am not getting.

Also please check https://gateoverflow.in/14043/what-is-the-relationship-between-weak-and-strong-entity

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see weak entity can not be identified by there own attribute so they need a strong entity by which they can be  discriminated. Ex: suppose there are two table employee table and dependent table a employee has employee id as the primary key but dependent table has no primary key so many dependent can be related to  same employee id but you can not relate two employee to same dependent.

so it is one to many i.e a strong entity can have many dependent(weak entity)