Let relations r1 (A, B, C) and r2 (C, D, E) have the following properties: r1 has

Question:

Let relations r1 (A, B, C) and r2 (C, D, E) have the following properties: r1 has 20,000 tuples, r2 has 45,000 tuples, 25 tuples of r1 fit on one block, and 30 tuples of r2 fit on one block. Estimate the number of block accesses required, using each of the following join strategies for r1 Θ r2:

a. Nested-loop joins

b. Block nested-loop joins

c. Merge joins

d. Hash joins