Given R = { Account , Analyst , Assets, Broker, Client, Commission, Company, Dividend, Exchange, Investment, Office, Profile, Return, Risk_profile, Stock, Volume} and a set of functional dependencies F{fd1, fd2,fd3, fd4, fd5,fd6, fd7, fd8, fd9, fd10, fd11} where:
fd1: Client - Office
fd2: Stock - Exchange, Dividend
fd3: Broker - Profile
fd4: Company - Stock
fd5: Client - Risk_profile, Analyst
fd6: Analyst - Broker
fd7: Stock, Broker - Invenstment, Volume
fd8: Stock - Company
fd9: Investment,Commission - Return
fd10: Stock, Broker - Client
fd11: Account - Assests
these are candidate key(s) :
(Account, Commission,Analyst ,Company)
(Account, Commission,Analyst ,Stock)
(Account ,Commission,Broker ,Company)
(Account ,Commission,Broker ,Stock)
(Account ,Commission,Client, Company)
(Account ,Commission,Client ,Stock)
(Q) Select a primary key and justify your choice ?
I was select
(Account ,Commission,Broker ,Stock) as a primary key ???
I chose that because it has the most direct dependencies compared to other ones. e.g. more attributes are functionally dependent on this primary key.
please check if my answer is it true ? or Not
I'm waiting your answer asap
thank you
