% Name: Bernard Ma
% Last 5 of ASU ID: 20989
% CSE412
% Professor Davulcu

% Question 1

topCDs2003 := project cdCode(select rating >= 1 and rating <= 5 and year = 2003(topCDs));
query1Ans := project cdCode, cdTitle, clientID, firstName, lastName, numberSold(((topCDs2003 njoin cd) njoin (rentedBy)) njoin client);

% Question 2

% Prints column of number sold for each cd published in 2003
sold2003 := project numberSold(select year = 2003(cd));

% Creates a copy of the query above and renames the label 'numberSold' so there are no duplicate attributes
sold2003v2 (numberSoldv2) := sold2003;

% Selects rows where sold2003 is smaller than sold2003v2. This nets all the unwanted rows (ones that aren't max)
unwantedNonMaxRows := project numberSold(select numberSold < numberSoldv2 (sold2003 product sold2003v2));

% Subtracts the original column from the unwanted columns to net the maximum of the column
sold2003Max := project numberSold(sold2003 difference unwantedNonMaxRows);