This question is about new database technology.NoSQL is a non-relational database that doesn't use SQL as a query language, and the data storage doesn't need a fixed table structure, and usually there is no join operation.NoSQL has the performance advantage of relational database in big data access, and it meets the requirements of data storage in horizontal scalability to meet the needs (especially for WEB applications). NoSQL has the performance advantages of a relational database in large data access, which can satisfy data storage requirements (especially WEB applications) in terms of horizontal scalability. At the same time, NoSQL does not need to meet the ACID, which needs to meet the Base (weak consistency theory, only the final consistency) can be