July2016 cs Q11

0. Consider the following ORACLE relations :
R (A, B, C) = {<1, 2, 3>, <1, 2, 0>, <1, 3, 1>, <6, 2, 3>, <1, 4, 2>, <3, 1, 4> }
S (B, C, D) = {<2, 3, 7>, <1, 4, 5>, <1, 2, 3>, <2, 3, 4>, <3, 1, 4>}.
Consider the following two SQL queries SQ1 and SQ2 :
SQ1 : SELECT R⋅B, AVG (S⋅B) FROM R, S WHERE R⋅A = S⋅C AND S⋅D < 7 GROUP BY R⋅B;
SQ2 : SELECT DISTINCT S⋅B, MIN (S⋅C) FROM S GROUP BY S⋅B HAVING COUNT (DISTINCT S⋅D) > 1;
If M is the number of tuples returned by SQ1 and N is the number of tuples returned by SQ2 then

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