Question

What is a hashing structure? What are the advantage(s) and disadvantage(s) associated with it?

Answer 1

What is hashing structure?

It is one of the methods of structuring the data in order to retrieve it fastly and efficiently.

In this structure, a hash table is first constructed. (Hash table is simply a data format wherein the data is stored in associative manner). Data is stored in the hash table in “array” format, so that each data value is associated with unique index value. The result is the key range of values are converted into a range of index.

Advantage of hashing structure:

1. Access of data is very fast, as the index of the data is known
2. Irrespective of the size of the data, insertions and search operation for particular data is very fast.

Disadvantages of hashing structure:

1. It is difficult to implement a hash table than self balancing binary search trees.
2. In open addressed hash tables, it is more prone to create poor hash functions.
3. It is not effective, when the number of entries are small.
4. It is a drawback in real time applications, as the insertion and deletion operation may take more time proportional to the number of entries.