Consider the table below of movie data. Each studio can produce many movies. A m
ID: 3691981 • Letter: C
Question
Consider the table below of movie data. Each studio can produce many movies. A movie can have many stars and a star may acts in many different movies. Find all functional dependencies between the attributes of this table. The table below lists customer/car hire data. Each customer may hire cars from various outlets throughout Glasgow. A car is registered at a particular outlet and can be hired out to a customer on a given date. Find all functional dependencies between the attributes of this tableExplanation / Answer
1.
Consider the relation between the attributes
movie={title, Year, Length, Genre, StudioName, StarName}
we can identify some Functional Dependencies as the following:
title, year-->Length
title, year-->StarName
However, note that
title,year--> AtarName may not always be true!
For example given the title of a movie and the year in which it was released, I can probably uniquely determine what is the length of that movie. Given a title and the year of release of a particular movie, I can probably determine what is the film type. Given a movie of a particular type, of a particular name and the year in which it was released, I can probably say well this is SciFi movie, this is a drama, this is a comedy whatever.
Similarly, I can probably also say the title, year uniquely determines to say film studioName. However title, year may not uniquely determine the star name that is the actors who star in that movie because there could be more than one actor who has stared in that movie and you cannot uniquely determine given the title and the year you cannot uniquely say well this is the movie star name who acted in that movie because it need not be complete, there could be other stars as well
2.
Consider the relation between the attributes
Car hire data={CarReg, hireData, Make, model, custNo, custName,outletNo,OutletLoc}
CarReg, hireDate-->OutletNo
CarReg, hireDate-->OutletLoc