3.5. Hash Tables

• Dictionary(special dist-it is created using hashing function)

• For Searching

• Fast data retrieval

• Used for caching and database indexing - Anything indexed means it has positions defined and we can directly jump on it and access it-we dont need to traverse the whole thing and reach - eg,array is indexed→to access a[4]→we dont need to traverse from 1 to 4 →we will allready jump to 4 since we allready know its position(4th)

• One certain column(most unique) is converted into hashed and other data is mapped to it