The physical relationship of a record is determined by a mathematical formula that transforms a file key into a record location in
Explanation
In database file organization, hashing is a technique used to map a key directly to a specific physical storage address (or bucket) using a mathematical function known as a hash function.
Hashed File: By applying a hash function H to a search key K, we can directly compute the address A where the record is stored:
A=H(K)
This allows for near-constant time O(1) access to records, as no searching through index tables or sequential lists is required.
Contrast with other methods:
B-tree/Indexed files: Use a tree-based or table-based structure where the system must traverse nodes to find the address.
Sequential files: Records are stored in a predefined physical order, requiring a linear search or binary search.
To summarize the efficiency of the lookup process in a hashed file:
Access Time≈O(1)
Mapping Process=Hash Function applied to Key
Because hashing explicitly uses a mathematical transformation to determine the physical location, it is the correct answer.
