Question

There is a blood bank which maintains two tables. DONOR, the people who are willing to donate blood and ACCEPTOR, the people who are in need of blood. The blood bank wants to place an order for some pints of blood with some other bank. To place such an order the bank needs to query their database and get the blood groups whose total amount that donors can give is less than the total amount of blood the acceptors need. List the blood groups and their unfulfilled quantities (needed-available) sorted by blood group,ascending.

Answer 1

Answer:

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