What do you mean by weak entity and partial key?Design an ER diagram for following scenario; In film industry, producers produce movies. Producers have their name, age and budget as attributes. They are uniquely identified by prod_id. All the movies have their title, year, and release date. No movie
What do you mean by weak entity and partial key?Design an ER diagram for following scenario; In film industry, producers produce movies. Producers have their name, age and budget as attributes. They are uniquely identified by prod_id. All the movies have their title, year, and release date. No movies can have same title. Every movies must be played by actor. An actor can play many movies. Actors have Fname and Lname to uniquely identify them. The actors have charge_rate as well. A single movie can have many producers and a producer can produce many movies.[3+7]
--- (a) Weak Entity and Partial Key A weak entity is an entity type that does not have a key attribute of its own. It cannot be uniquely identified by its own attributes alone. A weak entity depends on another entity (called the identifying entity or owner entity) for its existence and identifica...