Linear Hashing is a dynamically updateable diskbased index structure which implements a hashing scheme and which grows or shrinks one bucket at a time. The index is used to support exact match queries, i.e., find the record with a given key. Compared with the BC-tree index which also supports exact match queries (in logarithmic number of I/Os), Linear Hashing has better expected query cost O(1)...

Recent years have witnessed wide application of hashing for large-scale image retrieval. However, most existing hashing methods are based on hand-crafted features which might not be optimally compatible with the hashing procedure. Recently, deep hashing methods have been proposed to perform simultaneous feature learning and hashcode learning with deep neural networks, which have shown better pe...

4any current perfect hashing algorithms suffer from the problem of pattern collisions. In this paper, a perfect hashing technique that uses array-based tries and a simple sparse matrix packing algorithm is introduced. This technique eliminates all pattern collisions, and because of this it can be used to form ordered minimal perfect hash functions on extremely large word lists. This algorithm i...

The objective of this paper is to develop a high performance hash-based access method for main memory database systems. Chained bucket hashing is known to provide the fastest random access to a static file stored in main memory. For a dynamic file, however, chained bucket hashing is inappropriate because its address space cannot be adapted to the file size without total reorganization. Extendib...

Many applications use sequences of n consecutive symbols (n-grams). We review n-gram hashing and prove that recursive hash families are pairwise independent at best. We prove that hashing by irreducible polynomials is pairwise independent whereas hashing by cyclic polynomials is quasi-pairwise independent: we make it pairwise independent by discarding n− 1 bits. One application of hashing is to...

Hash functions are among the oldest and most widely used data structures in computer science. Different hash functions exist. So, it is very important to compare their performance. In this paper, we introduced our new hash function which was proposed recently in [1], and compared its performance with two different open addressing hashing algorithms: double hashing and exponential hashing. Doubl...

This paper discusses a generalised incremental hashing scheme for explicit state model checkers. The hashing scheme has been implemented into the model checker Spin. The incremental hashing scheme works for Spin’s exhaustive and both approximate verification modes: bitstate hashing and hash compaction. An implementation has been provided for 32-bit and 64-bit architectures. We performed extensi...

DEFINITION Linear Hashing is a dynamically updateable disk-based index structure which implements a hashing scheme and which grows or shrinks one bucket at a time. The index is used to support exact match queries, i.e. find the record with a given key. Compared with the B+-tree index which also supports exact match queries (in logarithmic number of I/Os), Linear Hashing has better expected quer...

Optimal search in main memory databases requires at most one key comparison to locate a record. Extendible hashing becomes impractical when it is adapted to yield optimal search in main memory databases because of its large directory size. Multi-directory hashing techniques can provide significantly improved directory utilization over extendible hashing. The objective of this paper is to analyz...