Suppose you have 2 relations, R(A,B) and S(B,C), with the following characteristics: The size of one disk block is 1000 bytes. Attributes A, B are of length 10 bytes. Attribute C is of length 180 bytes. The tuples are not spanned across disk blocks R = 5,000 (number of tuples of R) S = 500 (number of tuples of S) We have 30 blocks of memory buffer We use one disk block for one B+tree node Each pointer in a B+tree index (both a record pointer and a node pointer) uses 10 bytes. 4. (4 points) How many disk IOs would have been incurred if we used block nested loop join? Is it worthwhile to construct an index on S.B to perform the join using the above algorithm considering the index construction overhead? Suppose you have 2 relations, R(A,B) and S(B,C), with the following characteristics: The size of one disk block is 1000 bytes. Attributes A, B are of length 10 bytes. Attribute C is of length 180 bytes. The tuples are not spanned across disk blocks R = 5,000 (number of tuples of R) S = 500 (number of tuples of S) We have 30 blocks of memory buffer We use one disk block for one B+tree node Each pointer in a B+tree index (both a record pointer and a node pointer) uses 10 bytes. 4. (4 points) How many disk IOs would have been incurred if we used block nested loop join? Is it worthwhile to construct an index on S.B to perform the join using the above algorithm considering the index construction overhead