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Hash Table

A hash table applies a hash function to a key to pick a bucket, giving expected O(1) insert and lookup regardless of key order, with collisions handled by chaining or probing. It supports only equality lookups — there is no notion of range or order — which is why hash-based joins and indexes serve = but not <.

Questions this Concept answers

Why does a hash table need far less space than a direct access table storing the same keys?

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Hash Tables and Collision Handling in Data Structures

Hash tables are a data structure implementing the abstract dictionary interface—mapping keys to values with insert, delete, and search operations—by using a hash function to map keys from a large or …