Question

In a multiplex, movies are screened in different auditoriums. One movie can be shown in more than one auditorium. In order to maintain the record of movies, the multiplex maintains a relational database consisting of two relations viz. MOVIE and AUDI respectively as shown below:

Movie(Movie_ID, MovieName, ReleaseDate) Audi(AudiNo, Movie_ID, Seats, ScreenType, TicketPrice)

1. Is it correct to assign Movie_ID as the primary key in the MOVIE relation? If no, then suggest an appropriate primary key.
2. Is it correct to assign AudiNo as the primary key in the AUDI relation? If no, then suggest an appropriate primary key.
3. Is there any foreign key in any of these relations?

Answer 1

1. Yes because every movie will have its unique id.
2. Yes, because every auditorium will be assigned a unique id. No two auditoriums will have the same id.
3. Yes, Movie_ID in the Audi table is foreign because it references the Movie_ID in the Movie table.