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There are several relationships between tables: One to many Many to one one-on-one Many to many give an example: Users and orders are one to many Orders and users are many to one One user can place multiple orders Multiple orders belong to the same user The ID number is one to one. A person can only have one ID number. An ID nu ...

After building a complete SSM framework, I test the addition, deletion, modification and query of the database in the test class. The following is the test code: @Test public void insert() { ApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml"); EmployeeMapper employeeMappe ...

1, L2 cache configuration brief introduction The L2 cache is built on the L1 cache. When receiving a query request, MyBatis will first query the L2 cache. If the L2 cache is not alive In, query the first level cache again. If the first level cache does not exist, query the database again. graph LR A (L2 cache) - > b (L1 cache) - > C (dat ...

catalogue 1. Framework overview 1.1 three tier architecture 1.2 framework 2. Overview of mybatis framework 2.1 JDBC defects 2.2 overview of mybatis framework 3. Introduction case of mybatis 4. Introduction to main classes in mybatis 4.1 Resources class 4.2 SqlSessionFactoryBuilder class 4.3 SqlSessionFactory interface 4.4 SqlSession ...

L2 cache principle 1. L2 cache 1.1 definitions L2 cache is also called application level cache. Different from L1 cache, its scope is the whole application and can be used across threads. Therefore, L2 cache has a higher hit rate and is suitable for caching some data with less modification. When it comes to L2 cache, let's briefly talk ...

Preface: Hello, ladies and gentlemen, I'm running like a snail rz. Of course you can call me Snail Jun. I'm a beginner who has studied Java for more than half a year. At the same time, I have a great dream that I will become an excellent Java architect one day. This Mybatis Basic Learning series is used to record the whole process of my lea ...

1. Environmental construction 1.1 database files SET NAMES utf8mb4; SET FOREIGN_KEY_CHECKS = 0; -- ---------------------------- -- Table structure for user -- ---------------------------- DROP TABLE IF EXISTS `user`; CREATE TABLE `user` ( `id` int NOT NULL AUTO_INCREMENT COMMENT 'id Primary key', `username` varchar(20) CHARACTER SET ...

This paper is a dynamic node MyBatis tutorial My study notes. Chapter I 1. Three tier architecture (1) Functions of three layers User Interface Layer: accepts user data and displays the processing results of requests, including jsp, html, servlet, etc. Corresponding controller package; Business Logic Layer: accept the data passed from the ...

In the first article, we simply wrote and ran a general process of querying a certain data in the database. Now let's study the operation process of MyBatis. How does it run? Operation process 1. Detailed flow of code in test class          We all know that the entry of a program in Java is the main fu ...

3. XML mapper Create tables: user, shopping cart, goods DROP TABLE IF EXISTS `goods`; CREATE TABLE `goods` ( `good_id` int(11) NOT NULL AUTO_INCREMENT, `good_name` varchar(255) DEFAULT NULL, PRIMARY KEY (`good_id`) ) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci; -- ---------------------------- -- R ...