String Search Method Using N-Gram Segmentation and Appearance Lists
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing search methods are inefficient when searching across multiple indexes with plural search keys, as they do not effectively utilize index structures to speed up the search process.
Innovation Solution
A method that divides a search string into multiple characters or strings, groups documents into manageable blocks, and uses n-gram appearance lists and indexes to determine which blocks to perform a detailed search on, thereby reducing unnecessary search processing tasks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the n-gram method is used to search by checking appearance positions in indexes, then the search speed is improved compared to character-by-character searching, but the search efficiency deteriorates when searching across multiple indexes with plural search keys
Solution Approach 1:
The patent divides documents into blocks (segments) and creates appearance lists that indicate which blocks contain which n-grams. This segmentation allows the search system to quickly identify candidate blocks using the appearance list before performing detailed searches, thereby improving efficiency when searching across multiple indexes with plural search keys.
2Reliability
If detailed search is performed on all blocks, then search completeness is maintained, but computational load increases unnecessarily
Solution Approach 1:
The patent performs preliminary filtering by checking the appearance list to identify candidate blocks that contain all search keys before conducting detailed searches. This preliminary action eliminates blocks that cannot possibly match the search query, ensuring search completeness is maintained while significantly reducing the computational load of detailed searches.
3Measurement precision
If multiple indexes are searched sequentially, then all search keys are checked, but the search process becomes slower
Solution Approach 1:
The patent merges the search process for multiple indexes by using appearance lists to identify candidate blocks that satisfy all search keys simultaneously. Instead of sequentially searching each index and combining results, the system uses the appearance lists to directly identify blocks that match all search criteria, reducing search time while maintaining accuracy.
Data Source
AI summary
This string search method for a computer that searches documents for a specified string includes the following steps: a first step in which the specified string is divided into a plurality of characters or strings, including a first character or string and a second character or string; a second step in which a plurality of sets are created by grouping a plurality of documents in units; a third step in which a determination is made as to whether or not the first character or string appears in that set; a fourth step in which a determination is made as to whether or not the second character or string appears in that set; and a sixth step in which, if first appearance information and second appearance information were both added to one of the plurality of sets, namely a first set, a detailed search is performed on said first set.