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Exercise 8: MA.Hashing Design

Consider relation Person(name,gender,age) ...
pQ Query Type Q
0.5 select name from Person
where gender=X and age=Y
0.25 select age from Person
where name=X
0.25 select name from Person
where gender=X

Assume that all other query types have pQ=0.

Design a choice vector to minimise average selection cost.