hash table

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hash table

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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 or numeric sequences.

Hash tables are created with an algorithm that stores the keys into hash buckets, which contain 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, and the bucket is then compared to find the right key-value pair. See key-value pair, cryptographic hash function, DHT and hash total.


A Hash Table
When an item is looked up, its key is hashed into a bucket value, and the bucket is compared to find the key.
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References in periodicals archive ?
Since the current daemon implementation has not been carefully tuned, we expect substantial memory savings from techniques such as reductions in the storage costs of hash tables and more aggressive reaping of inactive structures.
Any one of the schemes can be used for internal hash tables as well.
Traditional approaches aiming at finding exact matches usually create indexes for the digests (using traditional hash functions like SHA-1, SHA-2, SHA-3, etc.) of the reference list and store them in sorted lists, balanced trees, or hash tables. The complexity of a single query in such cases is 0(log(r)) for sorted lists and trees and 0(1) for hash tables, which are lower than O(r) from the brute force similarity search.
Gupta, a consultant, corporate trainer, author, and speaker, outlines advanced SAS (Statistical Analysis System) programming techniques, procedures, and tools, such as PROC SQL, hash tables, and SAS Macro programming.
Yang Xu et al (2014) proposed multi-match packet classification rules formation algorithm with the help of distributed and pipelined hash tables and avoided the use of Ternary Content Addressable Memory and signature tree which consumed large amount of memory and time.
Rowstron, "Exploiting network proximity in distributed hash tables," FuDiCo, 2002.
Our Grid DBMS PORDaS is based on distributed hash tables (DHT).
Topics include software aging and rejuvenation in a SOAP-based server, congestion control for distributed hash tables, video-on- demand equipment allocation, and analysis models for blind search in unstructured overlays.
The implementation uses the method of the paper "Ordered Hash Tables" by Amble and Knuth (The Computer Journal 17 (May 1974), 135-142).
Most of the existing Data Lookup Systems employ lookup protocols that are based on the Distributed Hash Tables (DHTs).
The two primary application examples build a student information center and a chess game to illustrate the concepts of strings, class methods, sorting, inheritance, exceptions, logging, hash tables, input/output, mathematics classes, mock objects, multithreading, and generics.
McMillan (computer information systems, Pulaski Technical College) explains arrays, ArrayLists, linked lists, hash tables, dictionaries, trees, graphs, and sorting and searching with object-oriented representations.