During this Project, we study string similarity search based on edit distance that is supported by many database management systems like Oracle and PostgreSQL. Given the edit distance, ed(s, t), between two strings, s and t, the string similarity search is to search out each string t in a string database D which is almost like a query string s such that ed(s, t) = t for a given threshold t. Within the literature, most existing work takes a filter-and-verify approach, where the filter step is introduced to reduce the high verification cost of 2 strings by utilizing an index engineered offline for D. The two up-to-date approaches are prefix filtering and native filtering. We have a tendency to propose 2 new hash- primarily based labeling techniques, named OX label and XX label, for string similarity search. We have a tendency to assign a hash-label, H s , to a string s, and prune the dissimilar strings by comparing 2 hash-labels, H s and H t , for two strings s and t within the filter step. The key idea is to take the dissimilar bit- patterns between 2 hash-labels.Our hash-based mostly approaches achieve high efficiency, and keep its index size and index construction time one order of magnitude smaller than the present approaches in our experiment at the same time.
Efficiently Supporting Edit Distance Based String Similarity Search Using B $^+$-Trees
