Weak Entities

• A weak entity can be identified uniquely only by considering the primary key of another (owner) entity.

  • Owner entity set and weak entity set must participate in a one-to-many relationship set (1 owner, many weak entities).
  • Weak entity set must have total participation in this identifying relationship set.

lot

name

age

pname

Dependents

Employees

ssn

Policy

cost

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