dbms

Question

Answer 1

Answer should be option A.

As the first query selects all the pid's supplied by all the suppliers and the second query selects the pid's of parts which are supplied by everyone but not by Arun. And the operator between two queries is minus.

So the end result will display the pid's of parts supplied by Arun.

Answer 2

in the second table partidm should be replaced by pid. now first query will return pid of all parts and second query will replace all the pid of parts that have not  been supplied by arun so first - second =pid of parts that have been supplied by  arun

Answer 3

ans is (a)

pids of parts supplied by arun