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ShardingSphere + MySQL implementation sub database 1, About ShardingSphere ShardingSphere is an ecosystem composed of a set of open-source distributed database middleware solutions. It is composed of sharding JDBC, sharding proxy and sharding sidecar (planned). They all provide standardized data fragmentation, distributed transaction and data ...

Welcome to pay attention Python wechat ordering applet course video https://edu.csdn.net/course/detail/36074 Python practical quantitative transaction financial management system https://edu.csdn.net/course/detail/35475 1. Target scenario Tiktok or Kwai Fu, and so on, once a video is on fire, many UP owners will scramble to imitate or sho ...

1, How to set utf8mb4 up For string types in mysql, charset can be set exactly to the field. If only one field is set utf8mb4, other fields will not be affected. If it is set for the table, the existing field will still be utf8, and there will be more utf8 tags, and then the created field will be utf8mb4. If it is set for the library, the e ...

preface This article focuses on the most commonly used query data SELECT statement in SQL language. text 1. SELECT * FROM data_ table; --> from clause FROM declares that the data source for retrieving data is the data table SELECT keyword, followed by the column name to be retrieved, * represents all columns, and the number of column ...

Java cultivation program -- the 73rd day of learning punch in Java (72nd day of punch in) I've been busy with digital experiment recently. If you have any questions about verilog, please exchange and learn First, simply query the previous content. Query the top 200 cities in the city table. After grouping according to the Countr ...

This blog is equipped with the learning video of Lao Du in station B to make learning records for later learning and review. It is not used for other purposes. Video link: https://www.bilibili.com/video/BV1Vy4y1z7EX?spm_id_from=pageDriver Chapter 1 MySQL overview 1.1 Preface DB: database, warehouse for storing dataDBMS: database managem ...

catalogue Import   Why learn pandas What is pandas Basic operation of pandas Common data types of pandas Creation of pandas Series Series Slicing and indexing of pandas Reading external data from pandas DataFrame of pandas Row or column of pandas loc of pandas iloc of pandas Boolean index of pandas String method of pandas da ...

For code debugging, we can use any test code in the previous chapter as the Debug carrier. In this chapter, we actually study these two codes: InputStream xml = Resources.getResourceAsStream("mybatis-config.xml"); SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(xml); That is, how to load the MyBatis global ...

1, Basic command line operations mysql -u username - p password   ；--- Connect to database flush privileges ；   Refresh permissions show databases ； --- View all databases mysql > use   Database name--- Switch database mysql> show   tables ；--- Displays information for all tables in the database MySQL > ...

MyBatis If there is a problem, switch the version: jdk:1.8mysql:5.1.47maven 3.6.1IDEA brief introduction What is MyBatis MyBatis is an excellent persistence layer framework, which supports custom SQL, stored procedures and advanced mapping. MyBatis eliminates almost all JDBC code and the work of setting parameters and obtaining result ...