Consider a relation s(a, b) having 7 tuples such that 70 tuples fit into one disk block. suppose you can use 7 disk blocks in the buffer for sorting. give an estimate of the number of block ios needed for external merge sort on s

What type of file does a cookie place on web site visitors' computers so that web site managers can customize their sites to their visitors' preferences?

Suppose there is a relation r(a, b, c) with a b+-tree index with search keys (a, b).1. what is the worst-case cost of finding records satisfying 10 < a < 50 using this index, in terms of the number of records n1, retrieved and the height h of the tree? 2. what is the worst-case cost of finding records satisfying 10 < a < 50 and 5 < b < 10 using this index, in terms of the number of records n2 that satisfy this selection, as well as n1 and h defined above? 3. under what conditions on n1 and n2, would the index be an efficient way of finding records satisfying the condition from part (2)?

If you're using an existing powerpoint presentation that will receive new slides based on a word outline, select the a. slide that will appear after the new slides. b. first slide in the presentation. c. slide that will appear before the new slides. d. last slide in the presentation.