subject : database

Let Productspid price) and Sales(pid, date) be two relations; primary keys are underlined, pid is integer, prict is real and date is a string with format dd/mm/ yyyy. Products occupies 20,000 pages in no particular order. Saler. occupies 7,000 pages and is sorted in ascending pid order. Saler stores historical information for at least 3 years; sales are distributed uniformly over time. The memory buffer can fit 11 pages. Consider the following query; SEIECI DISTINCI * FROM Sales S, Products P WHERE S.pid = P.pid AND S.date =22/11/2009 Due to the application's constraints, the execution time of the query should not be longer than 5min. (Important if you cannot satisfy this constraint then your solution is wrong). Assume that an average I/O takes 10msec and ignore the CPU cost. The result is displayed on screen (i.e., it is not written on disk); ignore the cost to display the result. - Propose (verbally or pseudocode) an algorithm to exccute the query. - Prove that your algorithm can execute the query within the time limit