hash table

(redirected from Hashtable)

hash table

hash table

A lookup table that is designed to efficiently store non-contiguous keys (account numbers, part numbers, etc.) that may have wide gaps in their alphabetic and numeric sequences.

Hash tables are created by using a hashing function (algorithm) to hash the keys into hash buckets. Each bucket is a list of key value pairs. Since different keys may hash to the same bucket, the goal of hash table design is to spread out the key-value pairs evenly with each bucket containing as few key-value pairs as possible. When an item is looked up, its key is hashed to find the appropriate bucket. Then, the bucket is searched for the right key-value pair.

If access to the values is desired other than through the keys, an indexing system can be built on top of a hash table. Such user-level search engines can be made to handle imprecise queries and misspellings. See key-value pair and DHT.


A Hash Table
When an item is looked up, its key is hashed into a hash value that becomes the index into the bucket. Then, the bucket is searched for the right key-value pair.
References in periodicals archive ?
A hashtable is created which keeps track of a number of PropertyChangeListeners for Figs.
Some basic operations involved in this algorithm (and in Algorithm 2 and 3) include operation over stack, operation over hashtable and operation over vector.
For each query edge, if the twig is of P-C relationship, the parent and child details will be updated in the twigPC (a hashtable to store parent and child) repository as depicted in Figure 4.
Hashtable to store the relationship between customers and countries.
IDictionaryEnumerator to iterate through Hashtable keys.
Similar to a traditional hashtable data structure, other operations supported in the DHT include put and get.