Research And Implementation Of A Fuzzy Query Method For NoSQL Graph Database

With the emergence of large data,the NoSQL database has increased rapidly in Internet companies and enterprises because of its simplicity of design,good horizontal expansibility and better control of availability.NoSQL database is considered as a viable alternative to relational databases,because more and more organizations have realized that its pattern-free data model is a better way to deal with a large number of structured,semi-structured and unstructured data,for example,to use NoSQL graph databases to collect and store social media data.When making queries in the database,people sometimes cannot express their query requests and the database cannot handle inaccurate expressions such as "high people".It often leads to too many results to filter,even sometimes to inquire into the empty result set.In order to enable the database to query a statement with fuzzy conditions,it needs to expand the query language of the database so that it can handle fuzzy queries.The relational database has put forward a lot of methods for this research,however,there are few research work on the fuzzy query of NoSQL database at present.In view of the above problems,the main research work of this thesis is as follows:(1)A method of using the NoSQL graph database for fuzzy query expansion is proposed.This method extends the query language Cypher of the Neo4j graph database to realize the fuzzy query,mainly based on the node?attribute and relation of the graph,and add the fuzzy query extension condition to the keywords of START?WHERE?MATCH and RETURN in Cypher to realize fuzzy query extension,(2)A method of fuzzy query conversion is proposed,to convert the query language,it can transform the expanded query language with fuzzy conditions into an accurate general Cypher query language,so that it can accesses the data in the database directly,and then gets the desired results.Which can be realized by fuzzy query processing under simple conditions?fuzzy query processing with language variables and fuzzy query processing under complex conditions.(3)A fuzzy query system in Neo4j graph database have been designed and implemented.The feasibility and effectiveness of dealing with fuzzy queries on this system are illustrated through comparison and analysis,and the good performance of this system is verified through experiments of response time,recall and precision.