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Dynamic Hashing


The ‘Dynamic Hashing’ technique allows the hash function to be modified dynamically to accommodate the growth or shrinkage of the database. The ‘dynamic hashing’ technique we use is called ‘Extendible Hashing’.

This technique is used to know the address of the required record, whose key value is given.

The binary equivalent of the key is considered to map the key value to the address of the record.

A bucket concept is used here, whereas a bucket is some unit of memory to accommodate a certain number of records.

How to search a key:

  • First, the hash function of the key has to be calculated.
  • Next, we need to check how many bits are used in the directory, and these bits are called i.
  • Then, take the least significant i bits of the hash address. We can get the index of the directory with this.
  • Now we use the index, go to the directory and find the bucket address where the record can be there.

Reference Link

Dynamic Hashing