Question: 1. Consider the relation r (Key, Name, Address). The relation takes 100 blocks on disk and holds 10000 tuples. a. What is the selectivity of

1. Consider the relation r (Key, Name, Address). The relation takes 100 blocks on disk and holds 10000 tuples.

a. What is the selectivity of an equality predicate on Key?

b. Given a secondary Index_Name (height = 3) and a range predicate on Name with selectivity of 0.02, estimate the cost of doing the lookup on A.

c. Given a clustered Index_Name (height = 2) and a range predicate on Name with selectivity of 0.02, estimate the cost of doing the lookup on A.

d. Given a predicate P_A with selectivity of 0.3 and a predicate P_B with a selectivity of 0.5, what are the selectivities of:

(NOTE: you just need to compute the selectivity value, you do not need to estimate any costs in this part. You will have to make some assumptions about correlation between P_A and P_B)

NOT P_A
P_A AND P_B
P_A OR P_B
P_A AND (NOT P_B)

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2. How will you implement your chosen option and mitigate negative impact?

2. Did you have many choices, or were there constraints that narrowed your selection?