Suggest an efficient way to test if the bucket address table in extendable hashing can be reduced in size, by storing an extra count with the bucket address table. Give details of how the count should be maintained when buckets are split, coalesced or deleted. (Note: Reducing the size of the bucket address table is an expensive operation, and subsequent inserts may cause the table to grow again. Therefore, it is best not to reduce the size as soon as it is possible to do so, but instead do it only if the number of index entries becomes small compared to the bucket address table size.)
Answer to relevant QuestionsWhy is a hash structure not the best choice for a search key on which range queries are likely?Why is it not desirable to force users to make an explicit choice of a queryprocessing strategy? Are there cases in which it is desirable for users to be aware of the costs of competing query-processing strategies? Explain ...Estimate the number of block accesses required by your solution to Exercise for r1 Θ r2, where r1 and r2 are as defined in Exercise.Consider the relations r1 (A, B, C), r2 (C, D, E), and r3 (E, F) of Exercise. Assume that there are no primary keys, except the entire schema. Let V (C, r1) be 900, V (C, r2) be 1100, V (E, r2) be 50, and V (E, r3) be 100. ...Show that, if only left-deep join trees are considered, as in the System R optimizer, the time taken to find themost efficient join order is around n2n.Assume that there is only one interesting sort order.
Post your question