Suppose that the relation StarsIn discussed in Example 814

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Suppose that the relation StarsIn discussed in Example 8.14 required 100 pages rather than 10, but all other assumptions of that example continued to hold. Give formulas in terms of p_1 and p_2 to measure the cost of queries Q_1 and Q_2 and insertion I, under the four combinations of index/no index discussed there.

Solution

Action

No Index

Star Index

Movie Index

Both Indexes

Q1

100

4

100

4

Q2

100

100

4

4

I

2

4

4

6

Average

2 + 98p₁ + 98p₂

4+96p₂

4 + 96p₁

6 – 2p₁ – 2p₂

Explanation:

Action	No Index	Star Index	Movie Index	Both Indexes
Q1	100	4	100	4
Q2	100	100	4	4
I	2	4	4	6
Average	2 + 98p1 + 98p2	4+96p2	4 + 96p1	6 – 2p1 – 2p2