Question

Which of the following statements about hashing is false?

1. A good hash function maps similar data items or records to the same hash values.

2. A good hash function uniformly distributes data items across the entire set of possible hash values.

3. A perfect hash function allows for constant time search, insertion, and deletion, into and from a hash table.

4. When using an open addressing method of collision resolution, all data records reside in a single bucket array.

Please explain why.

Answer 1

Answer-A good hash function maps similar data items or records to the same values

Statement 1 is false. A good hash function generates very different hash values for similar data items or records.

In real world applications, many data sets contain very similar data elements. We would like these data elements to still be distributable over a hash table in order to get access to each of these items and avoid collision of values.Due to the possible applications of hash functions in data management and computer security,collision resolution is an important part of hashing